Home | Computer | Functions in C/C++ | Advantages of Functions in C/C++

Functions in C/C++ | Advantages of Functions in C/C++

September 6, 2022

A function is a block of code that performs a specific task or operation. In C++, functions can be defined using either the function declaration or function definition.

Functions are a powerful tool in C/C++ programming. They allow us to reuse code and reduce repetition. Functions can also be used to define classes or even entire programs.

Importance of Functions

A program may need multiple copies of the same piece of code. It may be required that certain actions be performed repeatedly. The program may grow large if functions are not utilized.

The piece of code repeated is stored in a separate subroutine. The real reason for using subroutines is to divide a program. These parts of a program can be managed easily

Advantages of functions in C/C++

Some important benefits or advantages of using functions are as follows: 

Easier to Code

A lengthy program can be divided into small functions. It is easier to write small functions instead of writing a long program. A function is written for a specific task. A programmer can focus the attention on a specific problem. It makes programming easier.

 Easier to Modify

Each function has a name and is written as a separate block. If there is an error in the program, it is corrected in the corresponding function. A small function is easy to modify than a large one.

Easier to Maintain & Debug

Functions are easier to maintain than long programs. Each function contains independent source code. A change in one part of the code does not affect other parts. In case of an error, the infected function is debugged only. The user does not need to examine the whole program.


Functions are like little machines – they take some input, perform an action on that input, and then return an output. You can think of them as reusable problem-solving code snippets that can make your life a lot easier as a programmer.

Because they can be executed many times, you can call a function whenever you need to solve the specific problem it was written for. This means that you don’t have to keep rewriting the same code over and over again – you can just call the function whenever you need it!

Suppose a function Line displays a line on the screen. It can be executed in different parts of the program to display the line repeatedly.

Less Programming Time

A program may be made up of many functions, which are written as independent programs. Different programmers can work on different functions simultaneously, which saves a lot of time in the long run.

Different types of functions in C/C++.

C/C++ language provides the following types of functions:

1. User-defined Functions

A type of function written by the programmer is known as a user-defined function.

A user-defined function has a unique name. A program may contain many user-defined functions. These functions are written according to the exact need of the user.

 2. Built-in Functions

A type of function that is available as a part of language is known as the built-in function or library function. These functions are ready-made programs. These functions are stored in different header files. Built-in functions make programming faster and easier.

C language provides many built-in functions to solve different problems. For example, clrscr is a built-in function to clear the screen. It is part of a header file called conio.h.

Process of writing a function in C/C++ language.

The process of writing a function in C language is very simple. A function consists of two parts known as function header and function body.

Syntax of C/C++

The basic syntax of the writing of a function is as follows: 

return-type function-name (parameters)




Function Header

The first line of a function definition is known as the function header. The following line shows the basic syntax of writing the function header.

return-type function-name (parameters)

The function header consists of the following elements:

return-type: It indicates the type of value that will be returned by the function.

function-name: It indicates the name of the function.

Parameters: re the values given to a function when the function is called.

Function Body

The set of statements that are executed inside the function is known as the function body. The body of function appears after the function header. The statements are written in curly braces (). The variable declaration and program logic are implemented in the function body. The arguments passed to a function can also be used in the body.

Frequently Asked Questions (FAQs)

What is a function in C/C++?

A function is a named block of code that performs some action. The statements written in a function are executed when it is called by its name.

What are the advantages of functions in C++?

·         Functions are easier to code and modify.
·         They are easier to maintain and debug.
·         They can be reused.

How many types of functions are there in C++?

C++ provides two types of functions.
User- defined function
Built-in function