class Solution {

 public:

     vector<int> twoSum(vector<int>& nums, int target) {

         vector<int> v;

         unordered_map<int, int> m;

         for(int i=;i<nums.size();++i)

         {

             int tt=target-nums[i];

             if(m.find(tt)!=m.end())

             {

                  v.push_back(m[tt]);

                 v.push_back(i);

                 return v;

             }

             else

                     m[nums[i]]=i;

         }

         //return v;

     }

 };