Reverse Integer

Description

Given a 32-bit signed integer, reverse digits of an integer.

Example 1:

Input: 123
Output: 321

Example 2:

Input: -123
Output: -321

Example 3:

Input: 120
Output: 21

Note:
Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−2³¹,  2³¹ − 1]. For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.

Solution(javascript)

/**
 * @param {number} x
 * @return {number}
 */
var reverse = function(y) {
    var reverseAbs = function(x){
        if (x == 0) return '';
        return x%10 + reverseAbs(Math.floor(x/10));
    }
    var limit = 2147483648;
    var rvsdY = reverseAbs(Math.abs(y));
    
    if(rvsdY > limit || y == 0) return 0;
    return parseInt((y < 0 ? '-' : '') + rvsdY);
};