C++ Program to Reverse a Number

Example to reverse an integer entered by the user in C++ programming. This problem is solved by using while loop in this example.

To understand this example, you should have the knowledge of following C++ programming topics:


Example: C++ Program to Reverse an Integer

#include <iostream>
using namespace std;

int main()
{
    int n, reversedNumber = 0, remainder;

    cout << "Enter an integer: ";
    cin >> n;

    while(n != 0)
    {
        remainder = n%10;
        reversedNumber = reversedNumber*10 + remainder;
        n /= 10;
    }

    cout << "Reversed Number = " << reversedNumber;

    return 0;
}

Output

Enter an integer: 12345
Reversed number = 54321

This program takes an integer input from the user and stores it in variable n.

Then the while loop is iterated until n != 0 is false.

In each iteration, the remainder when the value of n is divided by 10 is calculated, reversedNumber is computed and the value of n is decreased 10 fold.

Finally, the reversedNumber (which contains the reversed number) is printed on the screen.