[LeetCode] 9. Palindrome Number

Problem

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

class Solution {
    public boolean isPalindrome(int x) {
        if (x < 0) return false;
        if (x != 0 && x % 10 == 0) return false;
        int rvx = 0;
        int cpx = x;
        while (cpx != 0) {
            rvx = 10*rvx + cpx%10;
            cpx /= 10;
        }
        return rvx == x;
    }
}