C Program to Check Whether a Number is Palindrome or Not

An integer is a palindrome if the reverse of that number is equal to the original number.

Program to Check Palindrome

#include <stdio.h>
int main() {
  int n, reversed = 0, remainder, original;
    printf("Enter an integer: ");
    scanf("%d", &n);
    original = n;

    // reversed integer is stored in reversed variable
    while (n != 0) {
        remainder = n % 10;
        reversed = reversed * 10 + remainder;
        n /= 10;
    }

    // palindrome if orignal and reversed are equal
    if (original == reversed)
        printf("%d is a palindrome.", original);
    else
        printf("%d is not a palindrome.", original);

    return 0;
}

Output

Enter an integer: 1001
1001 is a palindrome.

Here, the user is asked to enter an integer. The number is stored in variable n.

We then assigned this number to another variable orignal. Then, the reverse of n is found and stored in reversed.

If original is equal to reversed, the number entered by the user is a palindrome.