LeetCode 260. Single Number III

class Solution {
public:
    vector<int> singleNumber(vector<int>& nums) {
        
        int num=0;
        for(int i=0;i<nums.size();i++)
        {
            num^=nums[i];
        }
        
        int x=1;
        while(num)
        {
            if(num&x)
            {
                break;
            }
            else
            {
                x<<=1;
            }
        }
        
        int a=0,b=0;
        
        for(int i=0;i<nums.size();i++)
        {
            if(nums[i]&x)
            {
                a^=nums[i];
            }
            else
                b^=nums[i];
        }
        
        vector<int> ans;
        ans.push_back(a);
        ans.push_back(b);
        return ans;
    }
};