Leetcode 349 Intersection of Two Arrays

Leetcode 349 Intersection of Two Arrays

#include <vector>#include <algorithm>#include <set>using namespace std;class Solution {public:    vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {    vector<int> result;    for(int num : nums1)    {        if(find(nums2.begin(),nums2.end(),num) != nums2.end())            result.push_back(num);//在num2中将其删掉就不用再去重了……    }    if(!result.empty())    {        sort(result.begin(),result.end());        auto iter = unique(result.begin(),result.end());//不去重不排序当然会快，笨蛋。        if(iter != result.end())            result.erase(iter,result.end());    }        return result;    }    vector<int> intersection2(vector<int>& nums1, vector<int>& nums2) {    vector<int> result;    unordered_set<int> s(nums1.begin(),nums1.end());//element is unique~ ATTENTION    for(int num : nums2)    {        if(s.find(num) != s.end())        {            result.push_back(num);            s.erase(num);        }    }    return result;    }};