Palindrome Number LeetCode Solution

We’ll check palindrome number or not by reversing the half of the number and if it is equal to the other half then the number is a palindrome number or else not.

Problem: https://leetcode.com/problems/palindrome-number/

class Solution { public: bool isPalindrome(int n) {

    // Negative numbers cannot be palindrome
    // Also if the last digit of the number is 0
    // the first digit of the number also needs to be 0
    // Only 0 satisfy this condition
    if(n < 0 || (n % 10 == 0 && n != 0)) {
        return false;
    }
    
    // if the reverse of half of the number is 
    // equal to the other half then it's a palindrome
    // When x > revnum, we've reached the middle of the number
    int revnum = 0;
    while(n > revnum) {
        revnum = (revnum \* 10) + (n % 10);
        n = n / 10;
    }
    
    // when length is an odd number, we need to get rid of the middle digit
    // since the middle digit doesn't matter in palindrome
    return n == revnum || n == revnum / 10;
    
}

};