leetcode 9 回文数

class Solution {
    public boolean isPalindrome(int x) {
        if(x < 0){
            return false;
        }
        int num = x;
        int value = 0;
        while(num > 0){
            value = value * 10 + num % 10;
            num = num / 10;
        }
        return value == x;

    }
}