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Single Number

Problem statement​

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 1:

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

Example 2:

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

Example 3:

Input: nums = [1]Output: 1

Constraints:

  • 1 <= nums.length <= 3 * 104
  • -3 * 104 <= nums[i] <= 3 * 104
  • Each element in the array appears twice except for one element which appears only once.

My solution​

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