User Define functions in C++

By Prof. Fazal Rehman Shamil
Last modified on August 29th, 2021

A function is a group of statements that together perform a task. Every C++ program has at least one compulsory function commonly known as the main() function.

How many types of function in C+?

There are two types of functions,

  1. the user defines
  2. built-in functions.

Built-in functions

Built-in functions are developed by the developers of the compiler when they develop the compiler software.

We just need to use them.

User defines functions

The user defines functions are needed to be declared, defined, and call by the user.

user defined functions C++

Simple C++ program to demonstrate User define  function

Output

11 Welcome to T4Tutorials.com

Dry Run and Explanation of User define  function with SMT

 

Flow of execution of User Define functions in C++
Flow of execution of User Define functions in C++
Which one executed first user defined function or main function
Which one executed first user defined function or main function

Advantages of user-defined functions- C++

  1. User-defined functions help us to divide a big program into smaller parts.
  2. The smaller parts of the program have the following benefits;
    • Easy to understand.
    • Easy to modify.
    • Easy to maintain.
    • Easy to debug.

Some important concepts you must know while working on user-defined functions are mentioned below;

  1. Call by value
  2. Call by reference 

User define function with an array

shamil memory table

Prof.Fazal Rehman Shamil (Available for Professional Discussions)
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