palindromenumber.js

//     Palindrome Number
//     Given an integer x, return true if x is palindrome integer.

//     An integer is a palindrome when it reads the same backward as forward. For example, 121 is palindrome while 123 is not.

//     Example 1:
//     Input: x = 121
//     Output: true

//     Example 2:
//     Input: x = -121
//     Output: false
//     Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
    
//     Example 3:
//     Input: x = 10
//     Output: false
//     Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
    
//     Example 4:
//     Input: x = -101
//     Output: false

var isPalindrome = function (x) {
  let output = null;
  if (x > 0) {
    let cv = x.toString().split("").reverse().join("");
    if (cv == x) {
      output = true;
    } else {
      output = false;
    }
  } else if (x == 0) {
    output = true;
  } else {
    output = false;
  }
  return output;
};