/**

* Reverse digits of an integer.

*

* Example1: x = 123, return 321

* Example2: x = -123, return -321

*

* Note:

* The input is assumed to be a 32-bit signed integer. Your function should return 0 when the reversed integer overflows.

*

* res.js

* @authors Joe Jiang ([email protected])

* @date 2017-02-21 21:25:59

* @version $Id$

*/

/**

* @param {number} x

* @return {number}

*/

var reverse = function(x) {

let res = 0,

abs = Math.abs(x),

negative = abs === x? false:true;

while (abs>0) {

let currentVal = abs % 10;

res = res*10 + currentVal;

abs = Number.parseInt(abs/10);

}

if (res > Math.pow(2, 31)) {

return 0;

} else if (negative) {

return -res;

}

return res;

};

// Another solution wrote in Java

//

// public int reverse(int x)

// {

// int result = 0;

// while (x != 0)

// {

// int tail = x % 10;

// int newResult = result * 10 + tail;

// if ((newResult - tail) / 10 != result)

// { return 0; }

// result = newResult;

// x = x / 10;

// }

// return result;

// }