Leetcode 349 Intersection of Two Arrays

Leetcode 349 Intersection of Two Arrays

#include 
#include 
#include 
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;
    }

};