Leetcode350

Given two arrays, write a function to compute their intersection.
Example 1:
Input: nums1 = [1,2,2,1], nums2 = [2,2]
Output: [2,2]
Example 2:
Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
Output: [4,9]
Note:
Each element in the result should appear as many times as it shows in both arrays.
The result can be in any order.

Solution:

#include <iostream>
#include <vector>
#include <map>

using namespace std;

class Solution{
public:
    vector<int> intersect(vector<int>& nums1, vector<int>& nums2) {

        map<int, int> record;
        for( int i = 0; i < nums1.size(); i++)
            record[nums1[i]] ++;

        vector<int> resultVector;
        for( int i = 0; i < nums2.size(); i++)
            if(record[nums2[i]] > 0) {
                resultVector.push_back(nums2[i]);
                record[nums2[i]]--;
            }

        return resultVector;

    }
};

总结：
注意和349题的区别。本题用了map 结构。