leetcode 349. Intersection of Two Arrays

Pick One

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.

解法：利用unordered_set实现

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