Leetcode 136 - Single number

Note:

  • Use XOR to find the extra.

Question:

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.

Example:

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Input: nums = [4,1,2,1,2]
Output: 4

Code:

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/**
* @param {number[]} nums
* @return {number}
*/
var singleNumber = function(nums) {
let res = 0;
for (const num of nums) {
res ^= num;
}
return res;
};