/**
 * @param {number} x
 * @return {boolean}
 */
var isPalindrome = function(x) {
    if (x < 0 || (!!x && x % 10 === 0)) {
        return false;
    }

    let reverseNum = 0;
    while (x > reverseNum) {
        reverseNum = reverseNum * 10 + x % 10;
        x = ~~(x/10);
    }
    // console.info(x, reverseNum);
    return x === reverseNum || x === ~~(reverseNum/10);
};

let nums = [0, 10, 121, 1001, 10001, 12021, 12212];
nums.forEach(n => {
    console.info(n, isPalindrome(n));
});