349. Intersection of Two Arrays(求两个数组的交集)

Given two arrays, write a function to compute their intersection.
Example:
Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].

Note:
Each element in the result must be unique.
The result can be in any order.

class Solution {
public:
    vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
        unordered_set<int> s(nums1.begin(),nums1.end());
        vector<int> res;
        for(auto i:nums2)
        {
            if(s.count(i))
            {
                res.push_back(i);
                s.erase(i);
            }
        }
        return res;
    }
};