C Program – Reverse a Number

C – Reverse a Number

To reverse a given integer in C programming, pop the last digit of the given number in a loop, and append it to a new number. At the end of iteration, we end up with the reversed number in the result.

C Program

In the following program, we read a number to n from user via console input, and reverse this number.

main.c

#include <stdio.h>

int main() {
    int n;
    printf("Enter a number : ");
    scanf("%d", &n);
    
    int reversed = 0;
    int temp = n;
    while (temp > 0) {
        reversed = (reversed * 10) + (temp % 10);
        temp = temp / 10;
    }
    
    printf("Reversed Number : %d\n", reversed);
}

Output

Enter a number : 1234
Reversed Number : 4321
Program ended with exit code: 0

Output

Enter a number : 4466
Reversed Number : 6644
Program ended with exit code: 0

We have used C While Loop to iterate over the digits of the given number.

Conclusion

In this C Tutorial, we learned how to reverse a number in C programming, with example programs.