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Given a signed 32-bit integer `x`, return `x` with its digits reversed. If reversing `x` causes the value to go outside the signed 32-bit integer range `[-231, 231 - 1]`, then return `0`.

Assume the environment does not allow you to store 64-bit integers (signed or unsigned).

Example 1:

```Input: x = 123
Output: 321
```

Example 2:

```Input: x = -123
Output: -321
```

Example 3:

```Input: x = 120
Output: 21
```

Example 4:

```Input: x = 0
Output: 0
```

Constraints:

• `-231 <= x <= 231 - 1`

Solution:

``````/**
* @param {number} x
* @return {number}
*/

var reverse = function(x) {
const str      = "" + Math.abs(x);   // convert absolute value to string
const reversed = str.split("")       // get array of digit characters
.reverse()            // reverse it
.join("");            // join into string again;
const num      = parseInt(reversed); // convert to integer
const revNum = Math.sign(x) * num;   // multiple the sign
// if out of range return 0
if (revNum < Math.pow(-2, 31) || revNum > Math.pow(2, 31) - 1) return 0;
return revNum;
}``````