C Program to Reverse a Number

Example to reverse an integer entered by the user. This problem is solved using while loop in this example.
C Program to Reverse a Number
C Program to Reverse a Number


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

Example: Reverse an Integer

#include <stdio.h>
int main()
{
    int n, reversedNumber = 0, remainder;

    printf("Enter an integer: ");
    scanf("%d", &n);

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

    printf("Reversed Number = %d", reversedNumber);

    return 0;
}

Output
Enter an integer: 2345
Reversed Number = 5432
This program takes an integer input from the user. Then the while loop is used until n != 0is false.
In each iteration of while loop, the remainder when n is divided by 10 is calculated and the value of n is reduced by times.

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