350. Intersection of Two Arrays II

 1 class Solution 
 2 {
 3 public:
 4     vector<int> intersect(vector<int>& nums1, vector<int>& nums2) 
 5     {
 6         vector<int> res;
 7         unordered_multiset<int> is(nums1.begin(),nums1.end());
 8         for(int i : nums2)
 9         {
10             auto p=is.find(i);
11             if(p!=is.end())
12             {
13                 res.push_back(i);
14                 is.erase(p);
15             }
16         }            
17         return res;
18     }
19 };