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.

Problem Link

Single Number - LeetCode

Code

class Solution {
public:
    int singleNumber(vector<int>& nums) {
        
        int Xor = 0;
        
        for(int ele:nums)
            Xor^=ele;
        
        return Xor;
    }
};