C++ Swap Two Numbers using a 3rd Variable

Hello Everyone!

In this tutorial, we will learn how to Swap two numbers using a 3rd variable, in the C++ programming language.

Code:

#include <iostream>
using namespace std;

int main()
{
    cout << "\n\nWelcome to Studytonight :-)\n\n\n";
    cout << " =====  Program to Swap two numbers using a 3rd variable ===== \n\n";

    //variable declaration
    int a,b,temp;

    //taking input from the command line (user)
    cout << "Enter the first number : ";
    cin >> a;

    cout << "Enter the second number : ";
    cin >> b;

    cout<<"\n\nValues Before Swapping:  \n"<<endl;
    cout<<"First Number = " << a <<endl;
    cout<<"Second Number = " << b <<endl;

    //Logic for swapping the two numbers using an extra variable 'temp'
    temp = a;
    a = b;
    b = temp;
    
    cout << "\n\nValues After Swapping:  \n"<<endl;
    cout << "First Number = " << a <<endl;
    cout << "Second Number = " << b <<endl;
    cout << "\n\n\n";

    return 0;
}

Output:

Now let's see what we have done in the above program.

Program Explained:

Let's break down the parts of the code for better understanding.

//Logic for swapping the two numbers using an extra variable 'temp'
temp = a;
a = b;
b = temp;

The logic involved here is that, similar to every other programming language, the variables in C++ stores the most recent value stored into it.

So, first we are putting the value of a in a new variable temp so that once b's value is assigned to a, the original value of a isn't lost.

Then we assign the original value of a to b, by making use of temp.

Keep Learning : )