Palindrome Number

Description

Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.

Example 1:

Input: 121
Output: true

Example 2:

Input: -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: 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.

Follow up:

Coud you solve it without converting the integer to a string?

Solution(javascript)

/**
 * @param {number} x
 * @return {boolean}
 */
const isPalindrome = function (x) {
  if (x < 0) {
    return false
  }
  let reverse = 0
  let num = x
  while (num > 0) {
    reverse = reverse * 10 + (num % 10)
    num = Math.floor(num / 10)
  }
  return reverse === x
}