349. Intersection of Two Arrays

Given two arrays, write a function to compute their intersection.

Example:
Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].

class Solution {
public:
    vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
        unordered_map<int,int>hash1;
        unordered_map<int,int>hash2;
        vector<int>res;
        
        for(int num : nums1){
            ++hash1[num];
        }

        for(int i =0;i<nums2.size();i++){
            if(--hash1[nums2[i]] >= 0){
                if(find(res.begin(),res.end(),nums2[i]) == res.end()){
                    res.push_back(nums2[i]);
                }
                
            }
        }
        
        return res;
        
        
    }
};