Problem - 2

Write a C++ program using functions to swap two values.

Solution :

#include <iostream>

#include <conio.h>

using namespace std;

void swap(int &, int &); // function prototype

int main()

{

int n,m;

cout<<"Enter your first number: ";

cin>>n;

cout<<"Enter your second number: ";

cin>>m;

cout<<"Your Numbers, Before swapping: "<<endl;

cout<<"First Number = "<<n<<endl;

cout<<"Second Number = "<<m<<endl;

swap(n,m); // function call by reference

cout<<"Your Numbers, After swapping"<<endl;

cout<<"First Number = "<<m<<endl;

cout<<"Second Number = "<<n<<endl;

getch();

return 0;

}

void swap(int &v, int &w) // function definition

{

v=v+w;

w=v-w;

v=v-w;

}

Output :

When you’ll compile this code, a console screen will pop up with a text:

Enter your first number:

After entering your first value, let’s say 169, your program will further ask you:

Enter your second number:

After you enter your second number, let’s say 29, your program will print:

Your Numbers, Before swapping

First Number = 169

Second Number = 29   

Your Numbers, After swapping

First Number = 29

Second Number = 169