Write a C++ program that explain the call by value functionality.

Write a C++ program that explain the call by value functionality.

Program Code:

#include <iostream>

using namespace std;

// function declaration 

void swap(int,int);

// main() function definition with function call

int main()

{

int a,b;

cout<<" Enter Value of first no is :";

cin>>a;

cout<<endl;

cout<<" Enter Value of second no is :";

cin>>b;

cout<<endl;

cout<<" Before swapping";

cout<<endl;

cout<<" Value of first no is : "<<a;

cout<<endl;

cout<<" Value of second no is : "<<b;

cout<<endl;

swap(a,b); // function call in main() function

cout<<endl;

cout<<" Outside function after swapping :";

cout<<endl;

cout<<" Value of first no is : "<<a;

cout<<endl;

cout<<" Value of second no is : "<<b; 

}

// user defined function definition

void swap(int a,int b)

{

int c;

c=a;

a=b;

b=c;

cout<<" Inside function after swapping :";

cout<<endl;

cout<<" Value of first no is : "<<a;

cout<<endl;

cout<<" Value of second no is : "<<b;

}

The program output is tested on www.jdoodle.com

Output:

Enter Value of first no is :

 Enter Value of second no is :

 Before swapping

 Value of first no is : 9

 Value of second no is : 8

 Inside function after swapping :

 Value of first no is : 8

 Value of second no is : 9

 Outside function after swapping :

 Value of first no is : 9

 Value of second no is : 8

Thanks

Mukesh Rajput