readme.md

Leetcode

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:

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

Solution

class Solution {
  public boolean isPalindrome(int x) {
    if (x < 0) return false;
    if (x < 10) return true;

    int y = x;
    int z = 0;

    while (y != 0) {
      z = z * 10 + y % 10;
      y = y / 10;
    }

    return x == z;
  }
}