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#136 - Single Number

Problem Description

Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.

You must implement a solution with a linear runtime complexity and use only constant extra space.

Solution

/**
 * @param {number[]} nums
 * @return {number}
 */
var singleNumber = function(nums) {
  return nums.reduce((result, num) => result ^= num, 0);
};