assignment in c language

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Assignment Operators in C

In C language, the assignment operator stores a certain value in an already declared variable. A variable in C can be assigned the value in the form of a literal, another variable, or an expression.

The value to be assigned forms the right-hand operand, whereas the variable to be assigned should be the operand to the left of the " = " symbol, which is defined as a simple assignment operator in C.

In addition, C has several augmented assignment operators.

The following table lists the assignment operators supported by the C language −

Simple Assignment Operator (=)

The = operator is one of the most frequently used operators in C. As per the ANSI C standard, all the variables must be declared in the beginning. Variable declaration after the first processing statement is not allowed.

You can declare a variable to be assigned a value later in the code, or you can initialize it at the time of declaration.

You can use a literal, another variable, or an expression in the assignment statement.

Once a variable of a certain type is declared, it cannot be assigned a value of any other type. In such a case the C compiler reports a type mismatch error.

In C, the expressions that refer to a memory location are called "lvalue" expressions. A lvalue may appear as either the left-hand or right-hand side of an assignment.

On the other hand, the term rvalue refers to a data value that is stored at some address in memory. A rvalue is an expression that cannot have a value assigned to it which means an rvalue may appear on the right-hand side but not on the left-hand side of an assignment.

Variables are lvalues and so they may appear on the left-hand side of an assignment. Numeric literals are rvalues and so they may not be assigned and cannot appear on the left-hand side. Take a look at the following valid and invalid statements −

Augmented Assignment Operators

In addition to the = operator, C allows you to combine arithmetic and bitwise operators with the = symbol to form augmented or compound assignment operator. The augmented operators offer a convenient shortcut for combining arithmetic or bitwise operation with assignment.

For example, the expression "a += b" has the same effect of performing "a + b" first and then assigning the result back to the variable "a".

Run the code and check its output −

Similarly, the expression "a <<= b" has the same effect of performing "a << b" first and then assigning the result back to the variable "a".

Here is a C program that demonstrates the use of assignment operators in C −

When you compile and execute the above program, it will produce the following result −

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C Assignment Operators

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An assignment operation assigns the value of the right-hand operand to the storage location named by the left-hand operand. Therefore, the left-hand operand of an assignment operation must be a modifiable l-value. After the assignment, an assignment expression has the value of the left operand but isn't an l-value.

assignment-expression :   conditional-expression   unary-expression assignment-operator assignment-expression

assignment-operator : one of   = *= /= %= += -= <<= >>= &= ^= |=

The assignment operators in C can both transform and assign values in a single operation. C provides the following assignment operators:

In assignment, the type of the right-hand value is converted to the type of the left-hand value, and the value is stored in the left operand after the assignment has taken place. The left operand must not be an array, a function, or a constant. The specific conversion path, which depends on the two types, is outlined in detail in Type Conversions .

• Assignment Operators

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Home » Learn C Programming from Scratch » C Assignment Operators

C Assignment Operators

Summary : in this tutorial, you’ll learn about the C assignment operators and how to use them effectively.

Introduction to the C assignment operators

An assignment operator assigns the vale of the right-hand operand to the left-hand operand. The following example uses the assignment operator (=) to assign 1 to the counter variable:

After the assignmment, the counter variable holds the number 1.

The following example adds 1 to the counter and assign the result to the counter:

The = assignment operator is called a simple assignment operator. It assigns the value of the left operand to the right operand.

Besides the simple assignment operator, C supports compound assignment operators. A compound assignment operator performs the operation specified by the additional operator and then assigns the result to the left operand.

The following example uses a compound-assignment operator (+=):

The expression:

is equivalent to the following expression:

The following table illustrates the compound-assignment operators in C:

• A simple assignment operator assigns the value of the left operand to the right operand.
• A compound assignment operator performs the operation specified by the additional operator and then assigns the result to the left operand.

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An operator is a symbol that operates on a value or a variable. For example: + is an operator to perform addition.

C has a wide range of operators to perform various operations.

C Arithmetic Operators

An arithmetic operator performs mathematical operations such as addition, subtraction, multiplication, division etc on numerical values (constants and variables).

Example 1: Arithmetic Operators

The operators + , - and * computes addition, subtraction, and multiplication respectively as you might have expected.

In normal calculation, 9/4 = 2.25 . However, the output is 2 in the program.

It is because both the variables a and b are integers. Hence, the output is also an integer. The compiler neglects the term after the decimal point and shows answer 2 instead of 2.25 .

The modulo operator % computes the remainder. When a=9 is divided by b=4 , the remainder is 1 . The % operator can only be used with integers.

Suppose a = 5.0 , b = 2.0 , c = 5 and d = 2 . Then in C programming,

C Increment and Decrement Operators

C programming has two operators increment ++ and decrement -- to change the value of an operand (constant or variable) by 1.

Increment ++ increases the value by 1 whereas decrement -- decreases the value by 1. These two operators are unary operators, meaning they only operate on a single operand.

Example 2: Increment and Decrement Operators

Here, the operators ++ and -- are used as prefixes. These two operators can also be used as postfixes like a++ and a-- . Visit this page to learn more about how increment and decrement operators work when used as postfix .

C Assignment Operators

An assignment operator is used for assigning a value to a variable. The most common assignment operator is =

Example 3: Assignment Operators

C relational operators.

A relational operator checks the relationship between two operands. If the relation is true, it returns 1; if the relation is false, it returns value 0.

Relational operators are used in decision making and loops .

Example 4: Relational Operators

C logical operators.

An expression containing logical operator returns either 0 or 1 depending upon whether expression results true or false. Logical operators are commonly used in decision making in C programming .

Example 5: Logical Operators

Explanation of logical operator program

• (a == b) && (c > 5) evaluates to 1 because both operands (a == b) and (c > b) is 1 (true).
• (a == b) && (c < b) evaluates to 0 because operand (c < b) is 0 (false).
• (a == b) || (c < b) evaluates to 1 because (a = b) is 1 (true).
• (a != b) || (c < b) evaluates to 0 because both operand (a != b) and (c < b) are 0 (false).
• !(a != b) evaluates to 1 because operand (a != b) is 0 (false). Hence, !(a != b) is 1 (true).
• !(a == b) evaluates to 0 because (a == b) is 1 (true). Hence, !(a == b) is 0 (false).

During computation, mathematical operations like: addition, subtraction, multiplication, division, etc are converted to bit-level which makes processing faster and saves power.

Bitwise operators are used in C programming to perform bit-level operations.

Visit bitwise operator in C to learn more.

Other Operators

Comma operator.

Comma operators are used to link related expressions together. For example:

The sizeof operator

The sizeof is a unary operator that returns the size of data (constants, variables, array, structure, etc).

Example 6: sizeof Operator

Other operators such as ternary operator ?: , reference operator & , dereference operator * and member selection operator  ->  will be discussed in later tutorials.

Table of Contents

• Arithmetic Operators
• Increment and Decrement Operators
• Assignment Operators
• Relational Operators
• Logical Operators
• sizeof Operator

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The C Programming Handbook for Beginners

C is one of the oldest, most widely known, and most influential programming languages.

It is used in many industries because it is a highly flexible and powerful language.

Learning C is a worthwhile endeavor – no matter your starting point or aspirations – because it builds a solid foundation in the skills you will need for the rest of your programming career.

It helps you understand how a computer works underneath the hood, such as how it stores and retrieves information and what the internal architecture looks like.

With that said, C can be a difficult language to learn, especially for beginners, as it can be cryptic.

This handbook aims to teach you C programming fundamentals and is written with the beginner programmer in mind.

There are no prerequisites, and no previous knowledge of any programming concepts is assumed.

If you have never programmed before and are a complete beginner, you have come to the right place.

Here is what you are going to learn in this handbook:

Chapter 1: Introduction to C Programming

• Chapter 2: Variables and Data Types in C
• Chapter 3: Operators in C
• Chapter 4: Conditional Statements in C
• Chapter 5: Loops in C
• Chapter 6: Arrays in C
• Chapter 7: Strings in C

Further learning: Advanced C Topics

Without further ado, let’s get started with learning C!

In this introductory chapter, you will learn the main characteristics and use cases of the C programming language.

You will also learn the basics of C syntax and familiarize yourself with the general structure of all C programs.

By the end of the chapter, you will have set up a development environment for C programming so you can follow along with the coding examples in this book on your local machine.

You will have successfully written, compiled, and executed your first simple C program that prints the text "Hello, world!" to the screen.

You will have also learned some core C language features, such as comments for documenting and explaining your code and escape sequences for representing nonprintable characters in text.

What Is Programming?

Computers are not that smart.

Even though they can process data tirelessly and can perform operations at a very high speed, they cannot think for themselves. They need someone to tell them what to do next.

Humans tell computers what to do and exactly how to do it by giving them detailed and step-by-step instructions to follow.

A collection of detailed instructions is known as a program.

Programming is the process of writing the collection of instructions that a computer can understand and execute to perform a specific task and solve a particular problem.

A programming language is used to write the instructions.

And the humans who write the instructions and supply them to the computer are known as programmers.

Low-level VS High-Level VS Middle-level Programming Languages – What's The Difference?

There are three types of programming languages: low-level languages, high-level languages, and middle-level languages.

Low-level languages include machine language (also known as binary) and assembly language.

Both languages provide little to no abstraction from the computer's hardware. The language instructions are closely related to or correspond directly to specific machine instructions.

This 'closeness to the machine' allows for speed, efficiency, less consumption of memory, and fine-grained control over the computer's hardware.

Machine language is the lowest level of programming languages.

The instructions consist of series of 0 s and 1 s that correspond directly to a particular computer’s instructions and locations memory.

Instructions are also directly executed by the computer’s processor.

Even though machine language was the language of choice for writing programs in the early days of computing, it is not a human-readable language and is time-consuming to write.

Assembly language allows the programmer to work closely with the machine on a slightly higher level.

It uses mnemonics and symbols that correspond directly to a particular machine’s instruction set instead of using sequences of 0 s and 1 s.

Next, high-level languages, like Python and JavaScript, are far removed from the instruction set of a particular machine architecture.

Their syntax resembles the English language, making them easier to work with and understand.

Programs written in high-level languages are also portable and machine-independent. That is, a program can run on any system that supports that language.

With that said, they tend to be slower, consume more memory, and make it harder to work with low-level hardware and systems because of how abstract they are.

Lastly, middle-level languages, like C and C++, act as a bridge between low-level and high-level programming languages.

They allow for closeness and a level of control over computer hardware. At the same time, they also offer a level of abstraction with instructions that are more human-readable and understandable for programmers to write.

What Is the C Programming Language?

C is a general-purpose and procedural programming language.

A procedural language is a type of programming language that follows a step-by-step approach to solving a problem.

It uses a series of instructions, otherwise known as procedures or functions, that are executed in a specific order to perform tasks and accomplish goals. These intructions tell the computer step by step what to do and in what order.

So, C programs are divided into smaller, more specific functions that accomplish a certain task and get executed sequentially, one after another, following a top-down approach.

This promotes code readability and maintainability.

A Brief History of the C Programming Language

C was developed in the early 1970s by Dennis Ritchie at AT&T Bell Laboratories.

The development of C was closely tied to the development of the Unix operating system at Bell Labs.

Historically, operating systems were typically written in Assembly language and without portability in mind.

During the development of Unix, there was a need for a more efficient and portable programming language for writing operating systems.

Dennis Ritchie went on to create a language called B, which was an evolution from an earlier language called BCPL (Basic Combined Programming Language).

It aimed to bridge the gap between the low-level capabilities of Assembly and the high-level languages used at the time, such as Fortran.

B was not powerful enough to support Unix development, so Dennis Ritchie developed a new language that took inspiration from B and BCPL and had some additional features. He named this language C.

C’s simple design, speed, efficiency, performance, and close relationship with a computer’s hardware made it an attractive choice for systems programming. This led to the Unix operating system being rewritten in C.

C Language Characteristics and Use Cases

Despite C being a relatively old language (compared to other, more modern, programming languages in use today), it has stood the test of time and still remains popular.

According to the TIOBE index , which measures the popularity of programming languages each month, C is the second most popular programming language as of August 2023.

This is because C is considered the "mother of programming languages" and is one of the most foundational languages of computer science.

Most modern and popular languages used today either use C under the hood or are inspired by it.

For example, Python’s default implementation and interpreter, CPython, is written in C. And languages such as C++ and C# are extensions of C and provide additional functionality.

Even though C was originally designed with systems programming in mind, it is widely used in many other areas of computing.

C programs are portable and easy to implement, meaning they can be executed across different platforms with minimal changes.

C also allows for efficient and direct memory manipulation and management, making it an ideal language for performance-critical applications.

And C provides higher-level abstractions along with low-level capabilities, which allows programmers to have fine-grained control over hardware resources when they need to.

These characteristics make C an ideal language for creating operating systems, embedded systems, system utilities, Internet of things (IoT) devices, database systems, and various other applications.

C is used pretty much everywhere today.

How to Set Up a Development Environment for C Programming on Your Local Machine

To start writing C programs on your local machine, you will need the following:

• A C Compiler
• An Integrated Development Environment (IDE)

C is a compiled programming language, like Go, Java, Swift, and Rust.

Compiled languages are different from interpeted languages, such as PHP, Ruby, Python, and JavaScript.

The difference between compiled and interpeted languages is that a compiled language is directly translated to machine code all at once.

This process is done by a special program called a compiler.

The compiler reads the entire source code, checks it for errors, and then translates the entire program into machine code. This is a language the computer can understand and it's directly associated with the particular instructions of the computer.

This process creates a standalone binary executable file containing sequences of 0 s and 1 s which is a more computer-friendly form of the initial source code. This file contains instructions that the computer can understand and run directly.

An interpeted language, on the other hand, doesn’t get translated into machine code all at once and doesn’t produce a binary executable file.

Instead, an interpreter reads and executes the source code one instruction at a time, line by line. The interpreter reads each line, translates it into machine code, and then immediately runs it.

If you are using a Unix or a Unix-like system such as macOS or Linux, you probably have the popular GNU Compiler Collection (GCC) already installed on your machine.

If you are running either of those operating systems, open the terminal application and type the following command:

If you're using macOS and have not installed the command line developer tools, a dialog box will pop-up asking you to install them – so if you see that, go ahead and do so.

If you have already installed the command line tools, you will see an output with the version of the compiler, which will look similar to the following:

If you are using Windows, you can check out Code::Blocks or look into installing Linux on Windows with WSL . Feel free to pick whatever programming environment works best for you.

An IDE is where you write, edit, save, run, and debug your C programs. You can think of it like a word processor but for writing code.

Visual Studio Code is a great editor for writing code, and offers many IDE-like features.

It is free, open-source, supports many programming languages, and is available for all operating systems.

Once you have downloaded Visual Studio Code, install the C/C++ extension .

It’s also a good idea to enable auto-saving by selecting: "File" -> "Auto Save".

If you want to learn more, you can look through the Visual Studio Code documentation for C/C++ .

With your local machine all set up, you are ready to write your first C program!

How to Write Your First C Program

To get started, open Visual Studio Code and create a new folder for your C program by navigating to "File" -> "Open" -> "New Folder".

Give this folder a name, for example, c-practice , and then select "Create" -> “Open".

You should now have the c-practice folder open in Visual Studio Code.

Inside the folder you just created, create a new C file.

Hold down the Command key and press N on macOS or hold down the Control and press N for Windows/Linux to create an Untitled-1 file.

Hold down the Command key and press S on macOS or hold down the Control key and press S for Windows/Linux, and save the file as a main.c file.

Finally, click "Save".

Make sure that you save the file you created with a .c extension, or it won’t be a valid C file.

You should now have the main.c file you just created open in Visual Studio Code.

Next, add the following code:

Let’s go over each line and explain what is happening in the program.

What Are Header Files in C?

Let’s start with the first line, #include <stdio.h> .

The #include part of #include <stdio.h> is a preprocessor command that tells the C compiler to include a file.

Specifically, it tells the compiler to include the stdio.h header file.

Header files are external libraries.

This means that some developers have written some functionality and features that are not included at the core of the C language.

By adding header files to your code, you get additional functionality that you can use in your programs without having to write the code from scratch.

The stdio.h header file stands for standard input-output.

It contains function definitions for input and output operations, such as functions for gathering user data and printing data to the console.

Specifically, it provides functions such as printf() and scanf() .

So, this line is necessary for the function we have later on in our program, printf() , to work.

If you don't include the stdio.h file at the top of your code, the compiler will not understand what the printf() function is.

What is the main() function in C?

Next, int main(void) {} is the main function and starting point of every C program.

It is the first thing that is called when the program is executed.

Every C program must include a main() function.

The int keyword in int main(void) {} indicates the return value of the main() function.

In this case, the function will return an integer number.

And the void keyword inside the main() function indicates that the function receives no arguments.

Anything inside the curly braces, {} , is considered the body of the function – here is where you include the code you want to write. Any code written here will always run first.

This line acts as a boilerplate and starting point for all C programs. It lets the computer know where to begin reading the code when it executes your programs.

What Are Comments in C?

In C programming, comments are lines of text that get ignored by the compiler.

Writing comments is a way to provide additional information and describe the logic, purpose, and functionality of your code.

Comments provide a way to document your code and make it more readable and understandable for anyone who will read and work with it.

Having comments in your source code is also helpful for your future self. So when you come back to the code in a few months and don't remember how the code works, these comments can help.

Comments are also helpful for debugging and troubleshooting. You can temporarily comment out lines of code to isolate problems.

This will allow you to ignore a section of code and concentrate on the piece of code you are testing and working on without having to delete anything.

There are two types of comments in C:

• Single-line comments
• Multi-line comments

Single-line comments start with two forward slashes, // , and continue until the end of the line.

Here is the syntax for creating a single-line comment in C:

Any text written after the forward slashes and on the same line gets ignored by the compiler.

Multi-line comments start with a forward slash, / , followed by an asterisk, * , and end with an asterisk, followed by a forward slash.

As the name suggests, they span multiple lines.

They offer a way to write slightly longer explanations or notes within your code and explain in more detail how it works.

Here is the syntax for creating a multi-line comment in C:

What is the printf() function in C?

Inside the function's body, the line printf("Hello, World!\n"); prints the text Hello, World! to the console (this text is also known as a string).

Whenever you want to display something, use the printf() function.

Surround the text you want to display in double quotation marks, "" , and make sure it is inside the parentheses of the printf() function.

The semicolon, ; , terminates the statement. All statements need to end with a semicolon in C, as it identifies the end of the statement.

You can think of a semicolon similar to how a full stop/period ends a sentence.

What Are Escape Sequences in C?

Did you notice the \n at the end of printf("Hello, World!\n"); ?

It's called an escape sequence, which means that it is a character that creates a newline and tells the cursor to move to the next line when it sees it.

In programming, an escape sequence is a combination of characters that represents a special character within a string.

They provide a way to include special characters that are difficult to represent directly in a string.

They consist of a backslash, \ , also known as the escape character, followed by one or more additional characters.

The escape sequence for a newline character is \n .

Another escape sequence is \t . The \t represrents a tab character, and will insert a space within a string.

How to Compile and Run Your first C Program

In the previous section, you wrote your first C program:

Any code you write in the C programming language is called source code.

Your computer doesn’t understand any of the C statements you have written, so this source code needs to be translated into a different format that the computer can understand. Here is where the compiler you installed earlier comes in handy.

The compiler will read the program and translate it into a format closer to the computer’s native language and make your program suitable for execution.

You will be able to see the output of your program, which should be Hello, world! .

The compilation of a C program consists of four steps: preprocessing, compilation, assembling, and linking.

The first step is preprocessing.

The preprocessor scans through the source code to find preprocessor directives, which are any lines that start with a # symbol, such as #include .

Once the preprocessor finds these lines, it substitutes them with something else.

For example, when the preprocessor finds the line #include <stdio.h> , the #include tells the preprocessor to include all the code from the stdio.h header file.

So, it replaces the #include <stdio.h> line with the actual contents of the stdio.h file.

The output of this phase is a modified version of the source code.

After preprocessing, the next step is the compilation phase, where the modified source code gets translated into the corresponding assembly code.

If there are any errors, compilation will fail, and you will need to fix the errors to continue.

The next step is the assembly phase, where the assembler converts the generated assembly code statements into machine code instructions.

The output of this phase is an object file, which contains the machine code instructions.

The last step is the linking phase.

Linking is the process of combining the object file generated from the assembly phase with any necessary libraries to create the final executable binary file.

Now, let’s go over the commands you need to enter to compile your main.c file.

In Visual Studio Code, open the built-in terminal by selecting "Terminal" -> "New Terminal".

Inside the terminal, enter the following command:

The gcc part of the command refers to the C compiler, and main.c is the file that contains the C code that you want to compile.

Next, enter the following command:

The ls command lists the contents of the current directory.

The output of this command shows an a.out file – this is the executable file containing the source code statements in their corresponding binary instructions.

The a.out is the default name of the executable file created during the compilation process.

To run this file, enter the following command:

This command tells the computer to look in the current directory, ./ , for a file named a.out .

The above command generates the following output:

You also have the option to name the executable file instead of leaving it with the default a.out name.

Say you wanted to name the executable file helloWorld .

If you wanted to do this, you would need to enter the following command:

This command with the -o option (which stands for output) tells the gcc compiler to create an executable file named helloWorld .

To run the new executable file that you just created, enter the following command:

This is the output of the above command:

Note that whenever you make a change to your source code file, you have to repeat the process of compiling and running your program from the beginning to see the changes you made.

Chapter 2: Variables and Data Types

In this chapter, you will learn the basics of variables and data types – the fundamental storage units that allow you to preserve and manipulate data in your programs.

By the end of this chapter, you will know how to declare and initialize variables.

You will also have learned about various data types available in C, such as integers, floating-point numbers, and characters, which dictate how information is processed and stored within a program's memory.

Finally, you'll have learned how to receive user input in your programs, and how to use constants to store values that you don't want to be changed.

What Is a Variable in C?

Variables store different kind of data in the computer's memory, and take up a certain amount of space.

By storing information in a variable, you can retrieve and manipule it, perform various calculations, or even use it to make decisions in your program.

The stored data is given a name, and that is how you are able to access it when you need it.

How to Declare Variables in C

Before you can use a variable, you need to declare it – this step lets the compiler know that it should allocate some memory for it.

C is a strongly typed language, so to declare a variable in C, you first need to specify the type of data the variable will hold, such as an integer to store a whole number, a floating-point number for numbers with decimal places, or a char for a single character.

That way, during compilation time, the compiler knows if the variable is able to perform the actions it was set out to do.

Once you have specified the data type, you give the variable a name.

The general syntax for declaring variables looks something like this:

Let's take the following example:

In the example above, I declared a variable named age that will hold integer values.

What Are the Naming Conventions for Variables in C?

When it comes to variable names, they must begin either with a letter or an underscore.

For example, age and _age are valid variable names.

Also, they can contain any uppercase or lowercase letters, numbers, or an underscore character. There can be no other special symbols besides an underscore.

Lastly, variable names are case-sensitive. For example, age is different from Age .

How to Initialize Variables in C

Once you've declared a variable, it is a good practice to intialize it, which involves assigning an initial value to the variable.

The general syntax for initialzing a variable looks like this:

The assignment operator, = , is used to assign the value to the variable_name .

Let's take the previous example and assign age a value:

I initialized the variable age by assigning it an integer value of 29 .

With that said, you can combine the initialization and declaration steps instead of performing them separately:

How to Update Variable Values in C

The values of variables can change.

For example, you can change the value of age without having to specify its type again.

Here is how you would change its value from 29 to 30 :

Note that the data type of the new value being assigned must match the declared data type of the variable.

If it doesn't, the program will not run as expected. The compiler will raise an error during compilation time.

What Are the Basic Data Types in C?

Data types specify the type of form that information can have in C programs. And they determine what kind of operations can be performed on that information.

There are various built-in data types in C such as char , int , and float .

Each of the data types requires different allocation of memory.

Before exploring each one in more detail, let’s first go over the difference between signed and unsigned data types in C.

Signed data types can represent both positive and negative values.

On the other hand, unsigned data types can represent only non-negative values (zero and positive values).

Wondering when to use signed and when to use unsigned data types?

Use signed data types when you need to represent both positive and negative values, such as when working with numbers that can have positive and negative variations.

And use unsigned data types when you want to ensure that a variable can only hold non-negative values, such as when dealing with quantities.

Now, let's look at C data types in more detail.

What Is the char Data Type in C?

The most basic data type in C is char .

It stands for "character" and it is one of the simplest and most fundamental data types in the C programming language.

You use it to store a single individual character such as an uppercase and lowercase letter of the ASCII (American Standard Code for Information Interchange) chart.

Some examples of char s are 'a' and 'Z' .

It can also store symbols such as '!' , and digits such as '7' .

Here is an example of how to create a variable that will hold a char value:

Notice how I used single quotation marks around the single character.

This is because you can't use double quotes when working with char s.

Double quotes are used for strings.

Regarding memory allocation, a signed char lets you store numbers ranging from [-128 to 127 ], and uses at least 1 byte (or 8 bits) of memory.

An unsigned char stores numbers ranging from [0 to 255] .

What Is the int Data Type in C?

An int is a an integer, which is also known as a whole number.

It can hold a positive or negative value or 0 , but it can't hold numbers that contain decimal points (like 3.5 ).

Some examples of integers are 0 , -3 ,and 9 .

Here is how you create a variable that will hold an int value:

When you declare an int , the computer allocates at least 2 bytes (or 16 bits) of memory.

With that said, on most modern systems, an int typically allocates 4 bytes (or 32 bits) of memory.

The range of available numbers for a signed int is [-32,768 to 32,767] when it takes up 2 bytes and [-2,147,483,648 to 2,147,483,647] when it takes up 4 bytes of memory.

The range of numbers for an unsigned int doesn't include any of the negative numbers in the range mentioned for signed int s.

So, the range of numbers for unsigned ints that take up 2 bytes of memory is [0 to 65,535] and the range is [0 to 4,294,967,295] for those that take up 4 bytes.

To represent smaller numbers, you can use another data type – the short int . It typically takes up 2 bytes (or 16 bits) of memory.

A signed short int allows for numbers in a range from [-32,768 to 32,767] .

An unsigned short int allows for numbers in a range from [0 to 65,535] .

Use a short when you want to work with smaller integers, or when memory optimisation is critically important.

If you need to work with larger integers, you can also use other data types like long int or long long int , which provide a larger range and higher precision.

A long int typically takes up at least 4 bytes of memory (or 32 bits).

The values for a signed long int range from [-2,147,483,648 to 2,147,483,647] .

And the values for an unsigned long int range from [0 to 4,294,967,295] .

The long long int data type is able to use even larger numbers than a long int . It usually takes up 8 bytes (or 64 bits) of memory.

A signed long long int allows for a range from [-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807]

And an unsigned long long int has a range of numbers from [0 to 18,446,744,073,709,551,615] .

What Is The float Data Type in C?

The float data type is used to hold numbers with a decimal value (which are also known as real numbers).

It holds 4 bytes (or 32 bits) of memory and it is a single-precision floating-point type.

Here is how you create a variable that will hold a float value:

A double is a floating point value and is the most commonly used floating-point data type in C.

It holds 8 bytes (or 64 bits) of memory, and it is a double-precision floating-point type.

Here is how you create a variable that will hold a double value:

When choosing which floating-point data type to use, consider the trade-off between memory usage and precision.

A float has less precision that a double but consumes less memory.

Use a float when memory usage is a concern (such as when working with a system with limited resources) or when you need to perform calculations where high precision is not critical.

If you require higher precision and accuracy for your calculations and memory usage is not critical, you can use a double .

What Are Format Codes in C?

Format codes are used in input and output functions, such as scanf() and printf() , respectively.

They act as placeholders and substitutes for variables.

Specifically, they specify the expected format of input and output.

They tell the program how to format or interpret the data being passed to or read from the scanf() and printf() functions.

The syntax for format codes is the % character and the format specifier for the data type of the variable.

In the example above, age is the variable in the program. It is of type int .

The format code – or placeholder – for integer values is %i . This indicates that an integer should be printed.

In the program's output, %i is replaced with the value of age , which is 29 .

Here is a table with the format specifiers for each data type:

How to Recieve User Input Using the scanf() Function

Earlier you saw how to print something to the console using the printf() function.

But what happens when you want to receive user input? This is where the scanf() function comes in.

The scanf() function reads user input, which is typically entered via a keyboard.

The user enters a value, presses the Enter key, and the value is saved in a variable.

The general syntax for using scanf() looks something similar to the following:

Let's break it down:

• format_string is the string that lets the computer know what to expect. It specifies the expected format of the input. For example, is it a word, a number, or something else?
• &variable is the pointer to the variable where you want to store the value gathered from the user input.

Let's take a look at an example of scanf() in action:

In the example above, I first have to include the stdio.h header file, which provides input and output functions in C.

Then, in the main() function, I declare a variable named number that will hold integer values. This variable will store the user input.

Then, I prompt the user to enter a number using the printf() function.

Next, I use scanf() to read and save the value that the user enters.

The format specifier %i lets the computer known that it should expect an integer input.

Note also the & symbol before the variable name. Forgetting to add it will cause an error.

Lastly, after receiving the input, I display the received value to the console using another printf() function.

What are Constants in C?

As you saw earlier on, variable values can be changed throughout the life of a program.

With that said, there may be times when you don’t want a value to be changed. This is where constants come in handy.

In C, a constant is a variable with a value that cannot be changed after declaration and during the program's execution.

You can create a constant in a similar way to how you create variables.

The differences between constants and variables is that with constants you have to use the const keyword before mentioning the data type.

And when working with constants, you should always specify a value.

The general syntax for declaring constants in C looks like this:

Here, data_type represents the data type of the constant, constant_name is the name you choose for the constant, and value is the value of the constant.

It is also best practice to use all upper case letters when declaring a constant’s name.

Let’s see an example of how to create a constant in C:

In this example, LUCKY_NUM is defined as a constant with a value of 7 .

The constant's name, LUCKY_NUM , is in uppercase letters, as this is a best practice and convention that improves the readability of your code and distinguishes constants from variables.

Once defined, it cannot be modified in the program.

If you try to change its value, the C compiler will generate an error indicating that you are attempting to modify a constant.

Chapter 3: Operators

Operators are essential building blocks in all programming languages.

They let you perform various operations on variables and values using symbols.

And they let you compare variables and values against each other for decision-making computatons.

In this chapter, you will learn about the most common operators in C programming.

You will first learn about arithmetic operators, which allow you to perform basic mathematical calculations.

You will then learn about relational (also known as comparisson operators), which help you compare values.

And you will learn about logical operators, which allow you to make decisions based on conditions.

After understanding these fundamental operators, you'll learn about some additional operators, such as assignment operators, and increment and decrement operators.

By the end of this chapter, you will have a solid grasp of how to use different operators to manipulate data.

What Are the Arithmetic Operators in C?

Arithmetic operators are used to perform basic arithmetic operations on numeric data types.

Operations include addition, subtraction, multiplication, division, and calculating the remainder after division.

These are the main arithmetic operators in C:

Let's see examples of each one in action.

How to Use the Addition ( + ) Operator

The addition operator adds two operands together and returns their sum.

How to Use the Subtraction ( - ) Operator

The subtraction operator subtracts the second operand from the first operand and returns their difference.

How to Use the Multiplication ( * ) Operator

The multiplication operator multiplies two operands and returns their product.

How to Use the Division ( / ) Operator

The division operator divides the first operand by the second operand and returns their quotient.

How to Use the Modulo ( % ) Operator

The modulo operator returns the remainder of the first operand when divided by the second operand.

The modulo operator is commonly used to determine whether an integer is even or odd.

If the remainder of the operation is 1 , then the integer is odd. If there is no remainder, then the integer is even.

What Are The Relational Operators in C?

Relational operators are used to compare values and return a result.

The result is a Boolean value. A Boolean value is either true (represented by 1 ) or false (represented by 0 ).

These operators are commonly used in decision-making statements such as if statements, and while loops.

These are the relational operators in C:

Let’s see an example of each one in action.

How to Use the Equal to ( == ) Operator

The equal to operator checks if two values are equal.

It essentially asks the question, "Are these two values equal?"

Note that you use the comparisson operator (two equal signs – == ) and not the assignment operator ( = ) which is used for assigning a value to a variable.

The result is 1 (true), because a and b are equal.

How to Use the Not equal to ( != ) Operator

The not equal to operator checks if two values are NOT equal.

The result is 1 (true), because a and b are not equal.

How to Use the Greater than ( > ) Operator

This operator compares two values to check if one is greater than the other.

The result is 1 (true), because a is greater than b .

How to Use the Less than ( < ) Operator

This operator compares two values to check if one is less than the other.

The result is 0 (false), because a is not less than b .

How to Use the Greater than or Equal to ( >= ) Operator

This operator compares two values to check if one is greater than or equal to the other.

The result is 1 (true), because a is equal to b .

How to Use the Less than or equal to ( <= ) Operator

This operator compares two values to check if one is less than or equal the other.

The result is 1 (true), because a is less than b .

Logical Operators

Logical operators operate on Boolean values and return a Boolean value.

Here are the logical operators used in C:

Let's go into more detail on each one in the following sections.

How to Use the AND ( && ) Operator

The logical AND ( && ) operator checks whether all operands are true .

The result is true only when all operands are true .

Here is the truth table for the AND ( && ) operator when you are working with two operands:

The result of (10 == 10) && (20 == 20) is true because both operands are true .

Let's look at another example:

The result of (10 == 20) && (20 == 20) is false because one of the operands is false .

When the first operand is false , the second operand is not evaluated (since there's no point - it's already determined that the first operand is false, so the result can only be false ).

How to Use the OR ( || ) Operator

The logical OR ( || ) operator checks if at least one of the operands is true .

The result is true only when at least one of the operands is true .

Here is the truth table for the OR ( || ) operator when you are working with two operands:

Let's look at an example:

The result of (10 == 20) || (20 == 20) is true because one of the operands is true .

The result of (20 == 20) || (10 == 20) is true because one of the operands is true

If the first operand is true , then the second operator is not evaluated.

How to Use the NOT ( ! ) Operator

The logical NOT ( ! ) operator negates the operand.

If the operand is true , it returns false .

And if it is false , it returns true .

You may want to use the NOT operator when when you want to flip the value of a condition and return the opposite of what the condition evaluates to.

Here is the truth table for the NOT( ! ) operator:

The result of !(10 == 10) is false .

The condition 10 == 10 is true , but the ! operator negates it so the result is false .

And let's look at another example:

The result of !(10 == 20) is true .

The condition 10 == 20 is false, but the ! operator negates it.

What Is the Assignement Operator in C?

The assignment operator is used to assign a value to a variable.

In the example above, the value 10 is assigned to the variable num using the assignment operator.

The assignment operator works by evaluating the expression on the right-hand side and then storing its result in the variable on the left-hand side.

The type of data assigned should match the data type of the variable.

How to Use Compound Assignment Operators

Compound assignment operators are shorthand notations.

They allow you to modify a variable by performing an operation on it and then storing the result of the operation back into the same variable in a single step.

This can make your code more concise and easier to read.

Some common compound assignment operators in C include:

• += : Addition and assignment
• = : Subtraction and assignment
• = : Multiplication and assignment
• /= : Division and assignment
• %= : Modulo and assignment

Let’s see an example of how the += operator works:

In the example above, I created a variable named num and assigned it an initial value of 10 .

I then wanted to increment the variable by 5 . To do this, I used the += compound operator.

The line num += 5 increments the value of num by 5, and the result (15) is stored back into num in one step.

Note that the num += 5; line works exactly the same as doing num = num + 5 , which would mean num = 10 + 5 , but with fewer lines of code.

What Are the Increment and Decrement Operators in C?

The increment ++ and decrement -- operators increment and decrement a variable by one, respectively.

Let’s look at an example of how to use the ++ operator:

The initial value of the variable num is 10 .

By using the ++ increment operator, the value of num is set to 11 .

This is like perfoming num = num + 1 but with less code.

The shorthand for decrementing a variable by one is -- .

If you wanted to decrement num by one, you would do the following:

By using the -- increment operator, the value of num is now set to 9 . This is like perfoming num = num - 1 .

Chapter 4: Conditional Statements

The examples you have seen so far all execute line by line, from top to bottom.

They are not flexible and dynamic and do not adapt according to user behavior or specific situations.

In this chapter, you will learn how to make decisions and control the flow of a program.

You get to set the rules on what happens next in your programs by setting conditions using conditional statements.

Conditional statements take a specific action based on the result of a comparisson that takes place.

The program will decide what the next steps should be based on whether the conditions are met or not.

Certain parts of the program may not run depending on the results or depending on certain user input. The user can go down different paths depending on the various forks in the road that come up during a program's life.

First, you will learn about the if statement – the foundational building block of decision-making in C.

You will also learn about the else if and else statements that are added to the if statement to provide additional flexibility to the program.

You will then learn about the ternary operator which allows you to condense decision-making logic into a single line of code and improve the readability of your program.

How to Create an if statement in C

The most basic conditional statement in C is the if statement.

It makes a decision based on a condition.

If the given condition evaluates to true only then is the code inside the if block executed.

If the given condition evaluates to false , the code inside the if block is ignored and skipped.

The general syntax for an if statement in C is the following:

In the above code, I created a variable named age that holds an integer value.

I then prompted the user to enter their age and stored the answer in the variable age .

Then, I created a condition that checks whether the value contained in the variable age is less than 18.

If so, I want a message printed to the console letting the user know that to proceed, the user should be at least 18 years of age.

When asked for my age and I enter 16 , I'd get the following output:

The condition ( age < 18 ) evaluates to true so the code in the if block executes.

Then, I re-compile and re-run the program.

This time, when asked for my age, say I enter 28 , but I don't get any output:

This is because the condition evaluates to false and therefore the body of the if block is skipped.

I have also not specified what should happen in the case that the user's age is greater than 18.

To specify what happens in case the user's age is greater than 18, I can use an if else statement.

How to Create an if else statement in C

You can add an else clause to an if statement to provide code that will execute only when the if statement evaluates to false .

The if else statement essentially means that " if this condition is true do the following thing, else do this thing instead".

If the condition inside the parentheses evaluates to true , the code inside the if block will execute.

But if that condition evaluates to false , the code inside the else block will execute.

The else keyword is the solution for when the if condition is false and the code inside the if block doesn't run. It provides an alternative.

The general syntax looks like this:

Now, let's revisit the example from the previous section, and specify what should happen if the user's age is greater than 18:

If the condition is true the code in the if block runs:

If the condition is false the code in the if block is skipped and the code in the else block runs instead:

How to Create an else if statement in C

But what happens when you want to have more than one condition to choose from?

If you wish to chose between more than one option you can introduce an else if statement.

An else if statement essentially means that "If this condition is true, do the following. If it isn't, do this instead. However, if none of the above are true and all else fails, finally do this."

The general syntax looks something like the following:

Let's see how an else if statement works.

Say you have the following example:

If the first if statement is true, the rest of the block will not run:

If the first if statement is false, then the program moves on to the next condition.

If that is true the code inside the else if block executes and the rest of the block doesn't run:

If both of the previous conditions are all false, then the last resort is the else block which is the one to execute:

How to Use the Ternary Operator in C

The ternary operator (also known as the conditional operator) allows you to write an if else statement with fewer lines of code.

It can provide a way of writing more readable and concise code and comes in handy when writing simple conditional expressions.

You would want to use it when you are making making simple decisions and want to keep your code concise and on one line.

However, it's best to stick to a regular if-else statement when you are dealing with more complex decisions as the ternary operator could make your code hard to read.

The general syntax for the ternary operator looks something similar to the following:

• condition is the condition you want to evaluate. This condition will evaluate to either true of false
• ? separates the condition from the two possible expressions
• expression_if_true is executed if the condition evaluates to true
• : separates the expression_if_true from the expression_if_false
• expression_if_false is executed if the condition evaluates to false .

Let's take a look at an example:

In the example above, the condition is (x > 5) .

If x is greater than 5, the condition evaluates to true . And when the condition is true , the value assigned to y will be 100 .

If the condition evaluates to false , the value assigned to y will be 200 .

So, since x is greater than 5 ( x = 10 ), y is assigned the value 100 .

Chapter 5: Loops

In this chapter you will learn about loops, which are essential for automating repetitive tasks without having to write the same code multiple times.

Loops allow you to execute a specific block of code instructions repeatedly over and over again until a certain condition is met.

You will learn about the different types of loops, such as the for , while and do-while loops, and understand their syntax and when you should use each one.

You will also learn about the break statement, which allows you to control the execution flow within loops in specific ways.

How to Create a for Loop in C

A for loop allows you to execute a block of code repeatedly based on a specified condition.

It's useful when you know how many times you want to repeat a certain action.

The general syntax for a for loop looks like this:

• initialization is the step where you initialize a loop control variable. It's typically used to set the starting point for your loop.
• condition is the condition that is evaluated before each iteration. If the condition is true , the loop continues. If it's false , the loop terminates. The loop will run as long as the condition remains true.
• increment/decrement is the part responsible for changing the loop control variable after each iteration. It can be an increment ( ++ ), a decrement ( -- ), or any other modification.
• Code to be executed in each iteration is the block of code inside the for loop's body that gets executed in each iteration if the condition is true .

Let's see an example of how a for loop works.

Say you want to print the numbers from 1 to 5 to the console:

In the example above, I first initialize the loop control variable i with a value of 1 .

The condition i <= 5 is true, so the loop's body is executed and "Iteration 1" is printed.

After each iteration, the value of i is incremented by 1 . So, i is incremented to 2 .

The condition is still true , so "Iteration 2" is printed.

The loop will continue as long as i is less than or equal to 5 .

When i becomes 6 , the condition evaluates to false and the loop terminates.

How to Create a while Loop in C

As you saw in the previous section, a for loop is used when you know the exact number of iterations you want the loop to perform.

The while loop is useful when you want to repeat an action based on a condition but don't know the exact number of iterations beforehand.

Here is the general syntax of a while loop:

With a while loop, the condition is evaluated before each iteration. If the condition is true , the loop continues. If it's false, the loop terminates.

The while loop will continue as long as the condition evaluates to true .

Something to note with while loops is that the code in the loop's body is not guaranteed to run even at least one time if a condition is not met.

Let's see an example of how a while loop works:

In the example above, I first initialize a variable count with a value of 1 .

Before it runs any code, the while loop checks a condition.

The condition count <= 5 is true because count is initially 1 . So, the loop's body is executed and "Iteration 1" is printed.

Then, count is incremented to 2 .

The loop will continue as long as count is less than or equal to 5.

This process continues until count becomes 6 , at which point the condition becomes false , and the loop terminates.

Something to be aware of when working with while loops is accidentally creating an infinite loop:

In this case the condition always evaluates to true .

After printing the line of code inside the curly braces, it continuously checks wether it should run the code again.

As the answer is always yes (since the condition it needs to check is always true each and every time), it runs the code again and again and again.

The way to stop the program and escape from the endless loop is running Ctrl C in the terminal.

How to Create a do-while Loop in C

As mentioned in the previous section, the code in the while loop's body is not guaranteed to run even at least one time if the condition is not met.

A do-while loop executes a block of code repeatedly for as long as a condition remains true .

However, in contrast to a while loop, it is guaranteed to run at least once, regardless of whether the condition is true or false from the beginning.

So, the do-while loop is useful when you want to ensure that the loop's body is executed at least once before the condition is checked.

The general syntax for a do-while loop looks like this:

Let's take a look at an example that demonstrates how a do-while loop works:

In the example above I initialize a variable count with a value of 1 .

A do-while loop first does something and then checks a condition.

So, the block of code inside the loop is executed at least one time.

The string "Iteration 1" is printed and then count is incremented to 2 .

The condition count <= 5 is then checked and it evaluates to true , so the loop continues.

After the iteration where count is 6 , the condition becomes false , and the loop terminates.

How to Use the break Statement in C

The break statement is used to immediately exit a loop and terminate its execution.

It's a control flow statement that allows you to interrupt the normal loop execution and move on to the code after the loop.

The break statement is especially useful when you want to exit a loop under specific conditions, even if the loop's termination condition hasn't been met.

You might use it when you encounter a certain value, or when a specific condition is met.

Here's how to use a break statement in a loop:

In the example above, a for loop is set to iterate from 1 to 10 .

Inside the loop, the current value of i is printed on each iteration.

There is also an if statement that checks if the current value of i matches the target value, which is set to 5 .

If i matches the target value, the if statement is triggered and a message is printed.

As a result, the break statement exits the current loop immediately and prematurely.

The program will continue executing the code that is after the loop.

Chapter 6: Arrays

Arrays offer a versatile and organized way to store multiple pieces of related data that are arranged in an ordered sequence.

They allow you to store multiple values of the same data type under a single identifier and perform repetitive tasks on each element.

In this chapter, you will learn how to declare and initialize arrays. You will also learn how to access individual elements within an array using index notation and modify them.

In addition, you will learn how to use loops to iterate through array elements and perform operations on each element.

How to Declare and Initialize an Array in C

To declare an array in C, you first specify the data type of the elements the array will store.

This means you can create arrays of type int , float , char , and so on.

You then specify the array's name, followed by the array's size in square brackets.

The size of the array is the number of elements that it can hold. This number must be a positive integer.

Keep in mind that arrays have a fixed size, and once declared, you cannot change it later on.

Here is the general syntax for declaring an array:

Here is how to declare an array of integers:

In the example above, I created an array named grades that can store 5 int numbers.

After declaring an array, you can initialize it with initial values.

To do this, use the assignment operator, = , followed by curly braces, {} .

The curly braces will enclose the values, and each value needs to be separated by a comma.

Here is how to initialize the grades array:

Keep in mind that the number of values should match the array size, otherwise you will encounter errors.

Something to note here is that you can also partially initialize the array:

In this case, the remaining two elements will be set to 0 .

Another way to initialize arrays is to omit the array's length inside the square brackets and only assign the initial values, like so:

In this example, the array's size is 5 because I assigned it 5 values.

How to Find the Length of an Array in C Using the sizeof() Operator

The sizeof operator comes in handy when you need to calculate the size of an array.

Let's see an example of the sizeof operator in action:

In the example above, sizeof(grades) calculates the total size of the array in bytes.

In this case, the array has five integers.

As mentioned in a previous chapter, on most modern systems an int typically occupies 4 bytes of memory. Therefore, the total size is 5 x 4 = 20 bytes of memory for the entire array.

Here is how you can check how much memory each int occupies using the sizeof operator:

The sizeof(grades[0]) calculates the size of a single element in bytes.

By dividing the total size of the array by the size of a single element, you can calculate the number of elements in the array, which is equal to the array's length:

How to Access Array Elements in C

You can access each element in an array by specifying its index or its position in the array.

Note that in C, indexing starts at 0 instead of 1 .

So, the index of the first element is 0 , the index of the second element is 1 , and so on.

The last element in an array has an index of array_size - 1 .

To access individual elements in the array, you specify the array's name followed by the element's index number inside square brackets ( [] ).

Let's take a look at the following example:

In the example above, to access each item from the integer array grades , I have to specify the array's name along with the item's position in the array inside square brackets.

Remember that the index starts from 0 , so grades[0] gives you the first element, grades[1] gives you the second element, and so on.

Note that if you try to access an element with an index number that is higher than array_size - 1 , the compiler will return a random number:

How to Modify Array Elements in C

Once you know how to access array elements, you can then modify them.

The general syntax for modifying an array element looks like this:

You can change the value of an element by assigning a new value to it using its index.

Let's take the grades array from earlier on:

Here is how you would change the value 75 to 85 :

When modifying arrays, keep in mind that the new value must match the declared data type of the array.

How to Loop Through an Array in C

By looping through an array, you can access and perform operations on each element sequentially.

The for loop is commonly used to iterate through arrays.

When using a for loop to loop through an array, you have to specify the index as the loop variable, and then use the index to access each array element.

The %i placeholders are replaced with the current index i and the value at that index in the grades array, respectively.

You can also use a while loop to iterate through an array:

When using a while loop to loop through an array, you will need an index variable, int i = 0 , to keep track of the current position in the array.

The loop checks the condition (i < 5) and prints the index of the grade as well as the actual grade value.

After each grade is shown, the variable i is increased by one, and the loop continues until it has shown all the grades in the list.

A do-while works in a similar way to the while loop, but it is useful when you want to ensure that the loop body is executed at least once before checking the condition:

You can also use the sizeof operator to loop through an array.

This method is particularly useful to ensure your loop doesn't exceed the array's length:

The line int length = sizeof(grades) / sizeof(grades[0]); calculates the length of the grades array.

The length is calculated by dividing the total size (in bytes) of the array by the size of a single element grades[0] . The result is stored in the length variable.

The loop then iterates through the array using this length value.

For each iteration, it prints the index i and the value of the grade at that index grades[i] .

Chapter 7: Strings

In the previous chapter, you learned the basics of arrays in C.

Now, it's time to learn about strings – a special kind of array.

Strings are everywhere in programming. They are used to represent names, messages, passwords, and more.

In this chapter, you will learn about strings in C and how they are stored as arrays of characters.

You'll also learn the fundamentals of string manipulation.

Specifically, you will learn how to find a string's length and how to copy, concatenate, and compare strings in C.

What Are Strings in C?

A string is a sequence of characters, like letters, numbers, or symbols, that are used to represent text.

In C, strings are actually arrays of characters. And each character in the string has a specific position within the array.

Another unique characteristic of strings in C is that at the end of every one, there is a hidden \0 character called the 'null terminator'.

This terminator lets the computer know where the string ends.

So, the string ' Hello ' in C is stored as ' Hello\0 ' in memory.

How to Create Strings in C

One way to create a string in C is to initialize an array of characters.

The array will contain the characters that make up the string.

Here is how you would initialize an array to create the string 'Hello':

Note how I specified that the array should store 6 characters despite Hello being only 5 characters long. This is due to the null operator.

Make sure to include the null terminator, \0 , as the last character to signify the end of the string.

Let's look at how you would create the string 'Hello world':

In this example, there is a space between the word 'Hello' and the word 'world'.

So, the array must include a blank space character.

To print the string, you use the printf() function, the %s format code and the name of the array:

Another way to create a string in C is to use a string literal.

In this case, you create an array of characters and then assign the string by enclosing it in double quotes:

With string literals, the null terminator ( \0 ) is implied.

Creating strings with string literals is easier, as you don't need to add the null terminator at the end. This method is also much more readable and requires less code.

However, you may want to use character arrays when you want to modify the string's content. String literals are read-only, meaning the content is fixed.

How to Manipulate Strings in C

C provides functions that allow you to perform operations on strings, such as copying, concatenating, and comparing, to name a few.

To use these functions, you first need to include the string.h header file by adding the line #include <string.h> at the top of your file.

How to Find the Length of a String in C

To calculate the length of a string, use the strlen() function:

The strlen() function will return the number of characters that make up the string.

Note that the result does not include the null terminator, \0 .

How to Copy a String in C

To copy one string into another one, you can use the strcpy() function.

You may want to copy a string in C when you need to make changes to it without modifying it. It comes in handy when you need to keep the original string's content intact.

The general syntax for the strcpy() function looks like this:

The strcpy() function copies original_string into destination_string , including the null terminator ( '\0' ).

One thing to note here is that you need to make sure the destination array has enough space for the original string:

The strcpy() function copies the original string into an empty array and returns the copied string, which also includes the null terminator character ( '\0' ).

How to Concatenate Strings in C

You can concatenate (add) two strings together by using the strcat() function.

The general syntax for the strcat() function looks something like the following:

The strcat() function takes the original string and adds it to the end of destination string.

Make sure that the destination_string has enough memory for the original_string .

Something to note here is that strcat() does not create a new string.

Instead, it modifies the original destination_string , by including the original_string at the end.

Let's see an example of how strcat() works:

How to Compare Strings in C

To compare two strings for equality, you can use the strcmp() function.

The general syntax for the strcmp() function looks like this:

The strcmp() function compares string1 with string2 and returns an integer.

If the return value of strcmp() is 0 , then it means the two strings are the same:

If the return value of strcmp() is less than 0 , then it means the first word comes before the second:

And if the return value of strcmp() is greater than 0 , then it means the first word comes after the second one:

While this handbook has covered a wide range of topics, there is still so much to learn, as programming is so vast.

Once you have built a solid foundation with the basics of C programming, you may want to explore more advanced concepts.

You may want to move on to learning about functions, for example. They allow you to write instructions for a specific task and reuse that code throughout your program.

You may also want to learn about pointers. Pointers in C are like arrows that show you where a specific piece of information is stored in the computer's memory.

Then, you may want to move on to learning about structures. They're like custom data containers that allow you to group different types of information under one name.

Lastly, you may want to learn how to work with files. Working with files in C allows you to read from and write to files. This is useful for tasks like saving user data, reading configuration settings, or sharing data between different programs.

These suggestions are not a definitive guide – just a few ideas for you to continue your C programming learning journey.

If you are interested in learning more, you can check out the following freeCodeCamp resources:

• C Programming Tutorial for Beginners
• Learn C Programming Using the Classic Book by Kernighan and Ritchie
• Unlock the Mysteries of Pointers in C

This marks the end of this introduction to the C programming language.

Thank you so much for sticking with it and making it until the end.

You learned how to work with variables, various data types, and operators.

You also learned how to write conditional statements and loops. And you learned the basics of working with arrays and strings.

Hopefully, you have gained a good understanding of some of the fundamentals of C programming, got some inspiration on what to learn next, and are excited to continue your programming journey.

Happy coding!

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Assignment operator in c.

Last Updated on June 23, 2023 by Prepbytes

This type of operator is employed for transforming and assigning values to variables within an operation. In an assignment operation, the right side represents a value, while the left side corresponds to a variable. It is essential that the value on the right side has the same data type as the variable on the left side. If this requirement is not fulfilled, the compiler will issue an error.

What is Assignment Operator in C language?

In C, the assignment operator serves the purpose of assigning a value to a variable. It is denoted by the equals sign (=) and plays a vital role in storing data within variables for further utilization in code. When using the assignment operator, the value present on the right-hand side is assigned to the variable on the left-hand side. This fundamental operation allows developers to store and manipulate data effectively throughout their programs.

Example of Assignment Operator in C

For example, consider the following line of code:

Types of Assignment Operators in C

Here is a list of the assignment operators that you can find in the C language:

Simple assignment operator (=): This is the basic assignment operator, which assigns the value on the right-hand side to the variable on the left-hand side.

Addition assignment operator (+=): This operator adds the value on the right-hand side to the variable on the left-hand side and assigns the result back to the variable.

x += 3; // Equivalent to x = x + 3; (adds 3 to the current value of "x" and assigns the result back to "x")

Subtraction assignment operator (-=): This operator subtracts the value on the right-hand side from the variable on the left-hand side and assigns the result back to the variable.

x -= 4; // Equivalent to x = x – 4; (subtracts 4 from the current value of "x" and assigns the result back to "x")

* Multiplication assignment operator ( =):** This operator multiplies the value on the right-hand side with the variable on the left-hand side and assigns the result back to the variable.

x = 2; // Equivalent to x = x 2; (multiplies the current value of "x" by 2 and assigns the result back to "x")

Division assignment operator (/=): This operator divides the variable on the left-hand side by the value on the right-hand side and assigns the result back to the variable.

x /= 2; // Equivalent to x = x / 2; (divides the current value of "x" by 2 and assigns the result back to "x")

Bitwise AND assignment (&=): The bitwise AND assignment operator "&=" performs a bitwise AND operation between the value on the left-hand side and the value on the right-hand side. It then assigns the result back to the left-hand side variable.

x &= 3; // Binary: 0011 // After bitwise AND assignment: x = 1 (Binary: 0001)

Bitwise OR assignment (|=): The bitwise OR assignment operator "|=" performs a bitwise OR operation between the value on the left-hand side and the value on the right-hand side. It then assigns the result back to the left-hand side variable.

x |= 3; // Binary: 0011 // After bitwise OR assignment: x = 7 (Binary: 0111)

Bitwise XOR assignment (^=): The bitwise XOR assignment operator "^=" performs a bitwise XOR operation between the value on the left-hand side and the value on the right-hand side. It then assigns the result back to the left-hand side variable.

x ^= 3; // Binary: 0011 // After bitwise XOR assignment: x = 6 (Binary: 0110)

Left shift assignment (<<=): The left shift assignment operator "<<=" shifts the bits of the value on the left-hand side to the left by the number of positions specified by the value on the right-hand side. It then assigns the result back to the left-hand side variable.

x <<= 2; // Binary: 010100 (Shifted left by 2 positions) // After left shift assignment: x = 20 (Binary: 10100)

Right shift assignment (>>=): The right shift assignment operator ">>=" shifts the bits of the value on the left-hand side to the right by the number of positions specified by the value on the right-hand side. It then assigns the result back to the left-hand side variable.

x >>= 2; // Binary: 101 (Shifted right by 2 positions) // After right shift assignment: x = 5 (Binary: 101)

Conclusion The assignment operator in C, denoted by the equals sign (=), is used to assign a value to a variable. It is a fundamental operation that allows programmers to store data in variables for further use in their code. In addition to the simple assignment operator, C provides compound assignment operators that combine arithmetic or bitwise operations with assignment, allowing for concise and efficient code.

FAQs related to Assignment Operator in C

Q1. Can I assign a value of one data type to a variable of another data type? In most cases, assigning a value of one data type to a variable of another data type will result in a warning or error from the compiler. It is generally recommended to assign values of compatible data types to variables.

Q2. What is the difference between the assignment operator (=) and the comparison operator (==)? The assignment operator (=) is used to assign a value to a variable, while the comparison operator (==) is used to check if two values are equal. It is important not to confuse these two operators.

Q3. Can I use multiple assignment operators in a single statement? No, it is not possible to use multiple assignment operators in a single statement. Each assignment operator should be used separately for assigning values to different variables.

Q4. Are there any limitations on the right-hand side value of the assignment operator? The right-hand side value of the assignment operator should be compatible with the data type of the left-hand side variable. If the data types are not compatible, it may lead to unexpected behavior or compiler errors.

Q5. Can I assign the result of an expression to a variable using the assignment operator? Yes, it is possible to assign the result of an expression to a variable using the assignment operator. For example, x = y + z; assigns the sum of y and z to the variable x.

Q6. What happens if I assign a value to an uninitialized variable? Assigning a value to an uninitialized variable will initialize it with the assigned value. However, it is considered good practice to explicitly initialize variables before using them to avoid potential bugs or unintended behavior.

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Assignment and shorthand assignment operator in C

Quick links.

• Shorthand assignment

Assignment operator is used to assign value to a variable (memory location). There is a single assignment operator = in C. It evaluates expression on right side of = symbol and assigns evaluated value to left side the variable.

For example consider the below assignment table.

The RHS of assignment operator must be a constant, expression or variable. Whereas LHS must be a variable (valid memory location).

Shorthand assignment operator

C supports a short variant of assignment operator called compound assignment or shorthand assignment. Shorthand assignment operator combines one of the arithmetic or bitwise operators with assignment operator.

For example, consider following C statements.

The above expression a = a + 2 is equivalent to a += 2 .

Similarly, there are many shorthand assignment operators. Below is a list of shorthand assignment operators in C.

C Functions

C structures, c operators.

Operators are used to perform operations on variables and values.

In the example below, we use the + operator to add together two values:

Although the + operator is often used to add together two values, like in the example above, it can also be used to add together a variable and a value, or a variable and another variable:

C divides the operators into the following groups:

• Arithmetic operators
• Assignment operators
• Comparison operators
• Logical operators
• Bitwise operators

Arithmetic Operators

Arithmetic operators are used to perform common mathematical operations.

Assignment Operators

Assignment operators are used to assign values to variables.

In the example below, we use the assignment operator ( = ) to assign the value 10 to a variable called x :

The addition assignment operator ( += ) adds a value to a variable:

A list of all assignment operators:

Comparison Operators

Comparison operators are used to compare two values (or variables). This is important in programming, because it helps us to find answers and make decisions.

The return value of a comparison is either 1 or 0 , which means true ( 1 ) or false ( 0 ). These values are known as Boolean values , and you will learn more about them in the Booleans and If..Else chapter.

Comparison operators are used to compare two values.

Note: The return value of a comparison is either true ( 1 ) or false ( 0 ).

In the following example, we use the greater than operator ( > ) to find out if 5 is greater than 3:

A list of all comparison operators:

Logical Operators

You can also test for true or false values with logical operators.

Logical operators are used to determine the logic between variables or values:

C Exercises

Test yourself with exercises.

Fill in the blanks to multiply 10 with 5 , and print the result:

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Assignment Statement in C

How to assign values to the variables? C provides an  assignment operator  for this purpose, assigning the value to a variable using assignment operator is known as an assignment statement in C.

The function of this operator is to assign the values or values in variables on right hand side of an expression to variables on the left hand side.

The syntax of the  assignment expression

Variable = constant / variable/ expression;

The data type of the variable on left hand side should match the data type of constant/variable/expression on right hand side with a few exceptions where automatic type conversions are possible.

Examples of assignment statements,

b = c ; /* b is assigned the value of c */ a = 9 ; /* a is assigned the value 9*/ b = c+5; /* b is assigned the value of expr c+5 */

The expression on the right hand side of the assignment statement can be:

An arithmetic expression; A relational expression; A logical expression; A mixed expression.

The above mentioned expressions are different in terms of the type of operators connecting the variables and constants on the right hand side of the variable. Arithmetic operators, relational

Arithmetic operators, relational operators and logical operators are discussed in the following sections.

For example, int a; float b,c ,avg, t; avg = (b+c) / 2; /*arithmetic expression */ a = b && c; /*logical expression*/ a = (b+c) && (b<c); /* mixed expression*/

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• Assignment Statement

An Assignment statement is a statement that is used to set a value to the variable name in a program .

Assignment statement allows a variable to hold different types of values during its program lifespan. Another way of understanding an assignment statement is, it stores a value in the memory location which is denoted by a variable name.

The symbol used in an assignment statement is called as an operator . The symbol is ‘=’ .

Note: The Assignment Operator should never be used for Equality purpose which is double equal sign ‘==’.

The Basic Syntax of Assignment Statement in a programming language is :

variable = expression ;

variable = variable name

expression = it could be either a direct value or a math expression/formula or a function call

Few programming languages such as Java, C, C++ require data type to be specified for the variable, so that it is easy to allocate memory space and store those values during program execution.

data_type variable_name = value ;

In the above-given examples, Variable ‘a’ is assigned a value in the same statement as per its defined data type. A data type is only declared for Variable ‘b’. In the 3 rd line of code, Variable ‘a’ is reassigned the value 25. The 4 th line of code assigns the value for Variable ‘b’.

Assignment Statement Forms

This is one of the most common forms of Assignment Statements. Here the Variable name is defined, initialized, and assigned a value in the same statement. This form is generally used when we want to use the Variable quite a few times and we do not want to change its value very frequently.

Tuple Assignment

Generally, we use this form when we want to define and assign values for more than 1 variable at the same time. This saves time and is an easy method. Note that here every individual variable has a different value assigned to it.

(Code In Python)

Sequence Assignment

(Code in Python)

Multiple-target Assignment or Chain Assignment

In this format, a single value is assigned to two or more variables.

Augmented Assignment

In this format, we use the combination of mathematical expressions and values for the Variable. Other augmented Assignment forms are: &=, -=, **=, etc.

Browse more Topics Under Data Types, Variables and Constants

• Concept of Data types
• Built-in Data Types
• Constants in Programing Language 
• Access Modifier
• Variables of Built-in-Datatypes
• Declaration/Initialization of Variables
• Type Modifier

Few Rules for Assignment Statement

Few Rules to be followed while writing the Assignment Statements are:

• Variable names must begin with a letter, underscore, non-number character. Each language has its own conventions.
• The Data type defined and the variable value must match.
• A variable name once defined can only be used once in the program. You cannot define it again to store other types of value.
• If you assign a new value to an existing variable, it will overwrite the previous value and assign the new value.

FAQs on Assignment Statement

Q1. Which of the following shows the syntax of an  assignment statement ?

• variablename = expression ;
• expression = variable ;
• datatype = variablename ;
• expression = datatype variable ;

Answer – Option A.

Q2. What is an expression ?

• Same as statement
• List of statements that make up a program
• Combination of literals, operators, variables, math formulas used to calculate a value
• Numbers expressed in digits

Answer – Option C.

Q3. What are the two steps that take place when an  assignment statement  is executed?

• Evaluate the expression, store the value in the variable
• Reserve memory, fill it with value
• Evaluate variable, store the result
• Store the value in the variable, evaluate the expression.

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C operator precedence.

The following table lists the precedence and associativity of C operators. Operators are listed top to bottom, in descending precedence.

• ↑ The operand of prefix ++ and -- can't be a type cast. This rule grammatically forbids some expressions that would be semantically invalid anyway. Some compilers ignore this rule and detect the invalidity semantically.
• ↑ The operand of sizeof can't be a type cast: the expression sizeof ( int ) * p is unambiguously interpreted as ( sizeof ( int ) ) * p , but not sizeof ( ( int ) * p ) .
• ↑ The expression in the middle of the conditional operator (between ? and : ) is parsed as if parenthesized: its precedence relative to ?: is ignored.
• ↑ Assignment operators' left operands must be unary (level-2 non-cast) expressions. This rule grammatically forbids some expressions that would be semantically invalid anyway. Many compilers ignore this rule and detect the invalidity semantically. For example, e = a < d ? a ++ : a = d is an expression that cannot be parsed because of this rule. However, many compilers ignore this rule and parse it as e = ( ( ( a < d ) ? ( a ++ ) : a ) = d ) , and then give an error because it is semantically invalid.

When parsing an expression, an operator which is listed on some row will be bound tighter (as if by parentheses) to its arguments than any operator that is listed on a row further below it. For example, the expression * p ++ is parsed as * ( p ++ ) , and not as ( * p ) ++ .

Operators that are in the same cell (there may be several rows of operators listed in a cell) are evaluated with the same precedence, in the given direction. For example, the expression a = b = c is parsed as a = ( b = c ) , and not as ( a = b ) = c because of right-to-left associativity.

[ edit ] Notes

Precedence and associativity are independent from order of evaluation .

The standard itself doesn't specify precedence levels. They are derived from the grammar.

In C++, the conditional operator has the same precedence as assignment operators, and prefix ++ and -- and assignment operators don't have the restrictions about their operands.

Associativity specification is redundant for unary operators and is only shown for completeness: unary prefix operators always associate right-to-left ( sizeof ++* p is sizeof ( ++ ( * p ) ) ) and unary postfix operators always associate left-to-right ( a [ 1 ] [ 2 ] ++ is ( ( a [ 1 ] ) [ 2 ] ) ++ ). Note that the associativity is meaningful for member access operators, even though they are grouped with unary postfix operators: a. b ++ is parsed ( a. b ) ++ and not a. ( b ++ ) .

[ edit ] References

• C17 standard (ISO/IEC 9899:2018):
• A.2.1 Expressions
• C11 standard (ISO/IEC 9899:2011):
• C99 standard (ISO/IEC 9899:1999):
• C89/C90 standard (ISO/IEC 9899:1990):
• A.1.2.1 Expressions

[ edit ] See also

Order of evaluation of operator arguments at run time.

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C - Bitwise OR and assignment operator

The Bitwise OR and assignment operator (|=) assigns the first operand a value equal to the result of Bitwise OR operation of two operands.

(x |= y) is equivalent to (x = x | y)

The Bitwise OR operator (|) is a binary operator which takes two bit patterns of equal length and performs the logical OR operation on each pair of corresponding bits. It returns 1 if either or both bits at the same position are 1, else returns 0.

The example below describes how bitwise OR operator works:

The code of using Bitwise OR operator (|) is given below:

The output of the above code will be:

Example: Find largest power of 2 less than or equal to given number

Consider an integer 1000. In the bit-wise format, it can be written as 1111101000. However, all bits are not written here. A complete representation will be 32 bit representation as given below:

Performing N |= (N>>i) operation, where i = 1, 2, 4, 8, 16 will change all right side bit to 1. When applied on 1000, the result in 32 bit representation is given below:

Adding one to this result and then right shifting the result by one place will give largest power of 2 less than or equal to 1000.

The below code will calculate the largest power of 2 less than or equal to given number.

The above code will give the following output:

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C Exercises – Practice Questions with Solutions for C Programming

The best way to learn C programming language is by hands-on practice. This C Exercise page contains the top 30 C exercise questions with solutions that are designed for both beginners and advanced programmers. It covers all major concepts like arrays, pointers, for-loop, and many more.

So, Keep it Up! Solve topic-wise C exercise questions to strengthen your weak topics.

C Programming Exercises

The following are the top 30 programming exercises with solutions to help you practice online and improve your coding efficiency in the C language. You can solve these questions online in GeeksforGeeks IDE.

Q1: Write a Program to Print “Hello World!” on the Console.

In this problem, you have to write a simple program that prints “Hello World!” on the console screen.

For Example,

Click here to view the solution.

Q2: write a program to find the sum of two numbers entered by the user..

In this problem, you have to write a program that adds two numbers and prints their sum on the console screen.

Q3: Write a Program to find the size of int, float, double, and char.

In this problem, you have to write a program to print the size of the variable.

Q4: Write a Program to Swap the values of two variables.

In this problem, you have to write a program that swaps the values of two variables that are entered by the user.

Swap two numbers

Q5: Write a Program to calculate Compound Interest.

In this problem, you have to write a program that takes principal, time, and rate as user input and calculates the compound interest.

Q6: Write a Program to check if the given number is Even or Odd.

In this problem, you have to write a program to check whether the given number is even or odd.

Q7: Write a Program to find the largest number among three numbers.

In this problem, you have to write a program to take three numbers from the user as input and print the largest number among them.

Q8: Write a Program to make a simple calculator.

In this problem, you have to write a program to make a simple calculator that accepts two operands and an operator to perform the calculation and prints the result.

Q9: Write a Program to find the factorial of a given number.

In this problem, you have to write a program to calculate the factorial (product of all the natural numbers less than or equal to the given number n) of a number entered by the user.

Q10: Write a Program to Convert Binary to Decimal.

In this problem, you have to write a program to convert the given binary number entered by the user into an equivalent decimal number.

Q11: Write a Program to print the Fibonacci series using recursion.

In this problem, you have to write a program to print the Fibonacci series(the sequence where each number is the sum of the previous two numbers of the sequence) till the number entered by the user using recursion.

Fibonacci Series

Q12: Write a Program to Calculate the Sum of Natural Numbers using recursion.

In this problem, you have to write a program to calculate the sum of natural numbers up to a given number n.

Q13: Write a Program to find the maximum and minimum of an Array.

In this problem, you have to write a program to find the maximum and the minimum element of the array of size N given by the user.

Q14: Write a Program to Reverse an Array.

In this problem, you have to write a program to reverse an array of size n entered by the user. Reversing an array means changing the order of elements so that the first element becomes the last element and the second element becomes the second last element and so on.

Reverse an array

Q15: Write a Program to rotate the array to the left.

In this problem, you have to write a program that takes an array arr[] of size N from the user and rotates the array to the left (counter-clockwise direction) by D steps, where D is a positive integer. 

Q16: Write a Program to remove duplicates from the Sorted array.

In this problem, you have to write a program that takes a sorted array arr[] of size N from the user and removes the duplicate elements from the array.

Q17: Write a Program to search elements in an array (using Binary Search).

In this problem, you have to write a program that takes an array arr[] of size N and a target value to be searched by the user. Search the target value using binary search if the target value is found print its index else print ‘element is not present in array ‘.

Q18: Write a Program to reverse a linked list.

In this problem, you have to write a program that takes a pointer to the head node of a linked list, you have to reverse the linked list and print the reversed linked list.

Q18: Write a Program to create a dynamic array in C.

In this problem, you have to write a program to create an array of size n dynamically then take n elements of an array one by one by the user. Print the array elements.

Q19: Write a Program to find the Transpose of a Matrix.

In this problem, you have to write a program to find the transpose of a matrix for a given matrix A with dimensions m x n and print the transposed matrix. The transpose of a matrix is formed by interchanging its rows with columns.

Q20: Write a Program to concatenate two strings.

In this problem, you have to write a program to read two strings str1 and str2 entered by the user and concatenate these two strings. Print the concatenated string.

Q21: Write a Program to check if the given string is a palindrome string or not.

In this problem, you have to write a program to read a string str entered by the user and check whether the string is palindrome or not. If the str is palindrome print ‘str is a palindrome’ else print ‘str is not a palindrome’. A string is said to be palindrome if the reverse of the string is the same as the string.

Q22: Write a program to print the first letter of each word.

In this problem, you have to write a simple program to read a string str entered by the user and print the first letter of each word in a string.

Q23: Write a program to reverse a string using recursion

In this problem, you have to write a program to read a string str entered by the user, and reverse that string means changing the order of characters in the string so that the last character becomes the first character of the string using recursion. 

reverse a string

Q24: Write a program to Print Half half-pyramid pattern.

In this problem, you have to write a simple program to read the number of rows (n) entered by the user and print the half-pyramid pattern of numbers. Half pyramid pattern looks like a right-angle triangle of numbers having a hypotenuse on the right side.

Q25: Write a program to print Pascal’s triangle pattern.

In this problem, you have to write a simple program to read the number of rows (n) entered by the user and print Pascal’s triangle pattern. Pascal’s Triangle is a pattern in which the first row has a single number 1 all rows begin and end with the number 1. The numbers in between are obtained by adding the two numbers directly above them in the previous row.

Pascal’s Triangle

Q26: Write a program to sort an array using Insertion Sort.

In this problem, you have to write a program that takes an array arr[] of size N from the user and sorts the array elements in ascending or descending order using insertion sort.

Q27: Write a program to sort an array using Quick Sort.

In this problem, you have to write a program that takes an array arr[] of size N from the user and sorts the array elements in ascending order using quick sort.

Q28: Write a program to sort an array of strings.

In this problem, you have to write a program that reads an array of strings in which all characters are of the same case entered by the user and sort them alphabetically. 

Q29: Write a program to copy the contents of one file to another file.

In this problem, you have to write a program that takes user input to enter the filenames for reading and writing. Read the contents of one file and copy the content to another file. If the file specified for reading does not exist or cannot be opened, display an error message “Cannot open file: file_name” and terminate the program else print “Content copied to file_name”

Q30: Write a program to store information on students using structure.

In this problem, you have to write a program that stores information about students using structure. The program should create various structures, each representing a student’s record. Initialize the records with sample data having data members’ Names, Roll Numbers, Ages, and Total Marks. Print the information for each student.

We hope after completing these C exercises you have gained a better understanding of C concepts. Learning C language is made easier with this exercise sheet as it helps you practice all major C concepts. Solving these C exercise questions will take you a step closer to becoming a C programmer.

Frequently Asked Questions (FAQs)

Q1. what are some common mistakes to avoid while doing c programming exercises.

Some of the most common mistakes made by beginners doing C programming exercises can include missing semicolons, bad logic loops, uninitialized pointers, and forgotten memory frees etc.

Q2. What are the best practices for beginners starting with C programming exercises?

Best practices for beginners starting with C programming exercises: Start with easy codes Practice consistently Be creative Think before you code Learn from mistakes Repeat!

Q3. How do I debug common errors in C programming exercises?

You can use the following methods to debug a code in C programming exercises Read the error message carefully Read code line by line Try isolating the error code Look for Missing elements, loops, pointers, etc Check error online

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Next: Unions , Previous: Overlaying Structures , Up: Structures   [ Contents ][ Index ]

15.13 Structure Assignment

Assignment operating on a structure type copies the structure. The left and right operands must have the same type. Here is an example:

Notionally, assignment on a structure type works by copying each of the fields. Thus, if any of the fields has the const qualifier, that structure type does not allow assignment:

See Assignment Expressions .

When a structure type has a field which is an array, as here,

structure assigment such as r1 = r2 copies array fields’ contents just as it copies all the other fields.

This is the only way in C that you can operate on the whole contents of a array with one operation: when the array is contained in a struct . You can’t copy the contents of the data field as an array, because

would convert the array objects (as always) to pointers to the zeroth elements of the arrays (of type struct record * ), and the assignment would be invalid because the left operand is not an lvalue.

• C All Exercises & Assignments

Write a C program to check whether a number is even or odd

Description:

Write a C program to check whether a number is even or odd.

Note: Even number is divided by 2 and give the remainder 0 but odd number is not divisible by 2 for eg. 4 is divisible by 2 and 9 is not divisible by 2.

Conditions:

• Create a variable with name of number.
• Take value from user for number variable.

Enter the Number=9 Number is Odd.

Write a C program to swap value of two variables using the third variable.

You need to create a C program to swap values of two variables using the third variable.

You can use a temp variable as a blank variable to swap the value of x and y.

• Take three variables for eg. x, y and temp.
• Swap the value of x and y variable.

Write a C program to check whether a user is eligible to vote or not.

You need to create a C program to check whether a user is eligible to vote or not.

• Minimum age required for voting is 18.
• You can use decision making statement.

Enter your age=28 User is eligible to vote

Write a C program to check whether an alphabet is Vowel or Consonant

You need to create a C program to check whether an alphabet is Vowel or Consonant.

• Create a character type variable with name of alphabet and take the value from the user.
• You can use conditional statements.

Enter an alphabet: O O is a vowel.

Write a C program to find the maximum number between three numbers

You need to write a C program to find the maximum number between three numbers.

• Create three variables in c with name of number1, number2 and number3
• Find out the maximum number using the nested if-else statement

Enter three numbers: 10 20 30 Number3 is max with value of 30

Write a C program to check whether number is positive, negative or zero

You need to write a C program to check whether number is positive, negative or zero

• Create variable with name of number and the value will taken by user or console
• Create this c program code using else if ladder statement

Enter a number : 10 10 is positive

Write a C program to calculate Electricity bill.

You need to write a C program to calculate electricity bill using if-else statements.

• For first 50 units – Rs. 3.50/unit
• For next 100 units – Rs. 4.00/unit
• For next 100 units – Rs. 5.20/unit
• For units above 250 – Rs. 6.50/unit
• You can use conditional statements.

Enter the units consumed=278.90 Electricity Bill=1282.84 Rupees

Write a C program to print 1 to 10 numbers using the while loop

You need to create a C program to print 1 to 10 numbers using the while loop

• Create a variable for the loop iteration
• Use increment operator in while loop

1 2 3 4 5 6 7 8 9 10

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Referees set for EURO 2024 adventure

Wednesday, May 15, 2024

Article summary

Tournament match officials gather at Frankfurt base camp to prepare for their month-long assignment.

Article top media content

Article body

Match officials selected for duty at UEFA EURO 2024 are ready for action after a two-day workshop in Frankfurt.

The event brought together the 19 selected referees and their assistants, as well as VARs and supporting officials, for an in-depth briefing a month ahead of the tournament, which runs from 14 June to 14 July.

The workshop was the first gathering of all 89 EURO 2024 officials, and a perfect opportunity to familiarise themselves with their tournament base camp, a country hotel complex just outside Frankfurt, selected as a convenient central location for travel to each of the ten match venues across the country.

The group, which also features a team of officials from Argentina thanks to UEFA's on-going collaboration with CONMEBOL, will spend more than one month together as they prepare for the 51 matches to come.

Such a high-profile tournament, the third-biggest sporting stage in the world, brings with it plenty of pressure to perform, but also represents a high point in officials' careers, a point Roberto Rosetti, UEFA's managing director of refereeing, was keen to emphasise.

"Welcome to Germany and congratulations on being here. You are at one of the best tournaments in the world, so enjoy these moments. They are among the most important and beautiful moments in all your life. I am fully convinced that this is the best list of referees ever for a football tournament. We are so proud of the names on this list and you must be proud to be here too."

Roberto Rosetti's message to EURO 2024 officials

"I was very pleased to be selected for EURO 2024, it is a big achievement and was one of my personal goals, but I am also aware that it is a big responsibility and the most difficult part is still to come. This workshop is the best way to prepare, all here together to receive the same messages in a focused, friendly environment."

François Letexier, EURO 2024 referee

During the workshop, the referees received wide-ranging updates around match organisation, medical, technology and integrity matters, but the main focus was on their roles across the all-important 90 minutes.

Protecting the image of the game

One of the key points on the agenda was how referees should manage player and coach behaviour during matches.

Rosetti published an open letter earlier this week detailing the importance of working with teams to present a positive image and set the right example for younger players and supporters.

It was a topic also discussed with team coaches at the recent finalists' briefing in Düsseldorf and with UEFA's Football Board, and presented once more to officials here in Frankfurt.

"We are talking about the image of the game. Players and coaches must respect our job and if they don’t, we will take action," Rosetti explained.

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To encourage respect and fair play, UEFA has issued a new directive for EURO 2024, whereby referees will speak directly with team captains to explain key decisions on the pitch. The directive will be discussed in detail with each of the 24 participating teams at their base camps ahead of the tournament.

Captain-referee cooperation at EURO 2024

To enhance fair play and respect at EURO 2024, referees will open a line of dialogue with to give information and explain key decisions to team captains, including what was discussed with VARs.

Only the captain should speak with the referee during thee clarifications and in a mutually respectful manner. The captain should take responsibility for his team-mates, asking them to respect the referee, keep their distance and not surround the match officials.

Where the captain is the goalkeeper and not close to the action, they should nominate a single outfield player to represent them during the referee's explanations. This player will be identified when team's match sheets are submitted 75 minutes prior to kick-off.

Elite-level fitness for a world-class competition

It is not just players that need to be in peak condition for EURO 2024. Match officials must also be ready for action at the highest level, prepared to run up to 13 kilometres per match at high intensity while making split-second decisions.

UEFA monitors officials' fitness throughout the season, providing bespoke training programmes and testing to ensure optimal performance. In Frankfurt, they were put through their paces by specialist fitness coaches with a series of drills aiming to keep them sharp ahead of the tournament.

"Referees and assistant referees have no choice. You need to be injury free, fresh and fit when you come to the tournament. Training quality has been very high and we are very confident that you are doing a good job."

Werner Helsen, UEFA referee fitness coach

VAR at UEFA EURO 2024

Rosetti and UEFA's refereeing team presented different match situations to the officials, discussing the occasions when interventions should take place.

UEFA's approach during the tournament will mirror that in our club competitions. VAR will not overrule referees' on-field decisions unless the video reviews shows evidence of a clear and obvious mistake, with the final call always being made by the referee.

It is a message Rosetti shared with team coaches in Düsseldorf last month, where he emphasised "minimum interference for maximum benefit", with referees urged to trust their judgment and make strong decisions on the field.

With this encouragement and confidence from UEFA's refereeing leaders ringing in their ears, officials now return home to complete their domestic, and in some cases, European club seasons, before they reconvene in Germany in early June. The countdown is well and truly on!

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