Given an array of integers, every element appearstwiceexcept for one. Find that single one.

Note:
Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?

tag: bit manipulation

class Solution {
    public int singleNumber(int[] nums) {
        int ans = 0;

        for (int num : nums){
            ans ^= num;
        }

        return ans;
    }
}