63 lines
1.3 KiB
JavaScript
63 lines
1.3 KiB
JavaScript
/*
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Given a 32-bit signed integer, reverse digits of an integer.
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Example 1:
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Input: 123
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Output: 321
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Example 2:
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Input: -123
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Output: -321
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Example 3:
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Input: 120
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Output: 21
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Note:
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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.
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*/
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const { assert } = require('../../util/js');
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/**
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* @param {number} x
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* @return {number}
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*/
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const reverse = function(x) {
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const MAX_INT = Math.pow(2,31) -1;
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const MIN_INT = Math.pow(2,31)* -1;
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const X = x.toString();
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const isNeg = X[0] === '-';
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let reverseIntegerString = X.split('').reverse().join('');
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const reverseInteger = isNeg ? parseInt(reverseIntegerString) * -1 : parseInt(reverseIntegerString);
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return (reverseInteger >= MAX_INT || reverseInteger <= MIN_INT) ? 0 : reverseInteger;
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};
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/* Test Case 1
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* Input: 123
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* Output: 321
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*/
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x = 123;
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sol = 321;
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assert(reverse(x) === sol, 'Output: 321');
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/* Test Case 2
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* Input: -123
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* Output: -321
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*/
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x = -123;
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sol = -321
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assert(reverse(x) === sol, 'Output: -321');
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/* Test Case 3
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* Input: 120
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* Output: 21
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*/
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x = 120;
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sol = 21;
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assert(reverse(x) == sol, 'Output: 21');
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