C Exercises: Check whether an integer is a palindrome or not

C Programming Mathematics: Exercise-2 with Solution

Write a C program to check whether an integer is a palindrome or not. An integer is a palindrome when it reads the same forward as backward.

Example:
Input:
i = 1221
i = -121
i = 100
Output:
Is Palindrome: 1
Is Palindrome: 0
Is Palindrome: 0

Pictorial Presentation:

Sample Solution:

C Code:

#include <stdio.h>
#include <stdbool.h>

bool is_Palindrome(int i) {
    int n, d, y = 0;
    
    if (i < 0) 
	return false;
    
    n = i;
    while (n) {
        d = n % 10;
        if (y > (0x7fffffff - d) / 10) 
		return false;   
        y = y * 10 + d;
        n = n / 10;
    }
    
    return (y == i);
}

int main(void)
{
    int i = 1221;
    printf("Original integer: %d  ",i);
    printf("\nIs Palindrome: %d  ",is_Palindrome(i));
    i = -121;
    printf("\nOriginal integer: %d  ",i);
    printf("\nIs Palindrome: %d  ",is_Palindrome(i));
    i = 100;
    printf("\nOriginal integer: %d  ",i);
    printf("\nIs Palindrome: %d  ",is_Palindrome(i));
    return 0;
}

Sample Output:

Original integer: 1221  
Is Palindrome: 1  
Original integer: -121  
Is Palindrome: 0  
Original integer: 100  
Is Palindrome: 0  

Flowchart:

C Programming Code Editor:

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