How to write a C program to find whether a number is Palindrome or not

C Palindrome or Not

What is Palindrome Number?

A palindrome number is a number that remains the same when its digits are reversed. For Example : 11 is a palindrome number

Examples

Here is some palindrome numbers for reference.

Number	Palindrome or Not
11	is a palindrome
101	is a palindrome
1001	is a palindrome
10001	is a palindrome

C Program - Palindrome

Let's write a c program to check whether user entered number is a palindrome or not.

c-palindrome.c

#include <stdio.h>
int main()
{
int a, b, c, num;
printf("Enter a number : ");
scanf("%d",&num);
a = num;
b = 0;
while(num > 0)
{
c = num % 10;
b = (b * 10) + c;
num = num / 10;
}
if(a == b)
printf("\n%d is a Palindrome number", a);
else
printf("\n%d is not a Palindrome number", a);
return 0;
}

Enter a number : 1001
1001 is a Palindrome number

Note:

In the above program, we parse the user entered number by 10, so that remainder will be last number which is appended to a dummy variable b. Finally, variable b is compared to the user entered number to check whether they are equal, if so the number is said to be palindrome number else it's not a palindrome number.