Two Pointers-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].

Note:

• Each element in the result must be unique.
• The result can be in any order.

  • class Solution {
    public:
        vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
            unordered_map<int, bool> hash;
            vector<int> result;
            for(auto val: nums1) hash[val] = true;
            for(auto val: nums2)
                if(hash.count(val))
                {
                    result.push_back(val);
                    hash.erase(val);
                }
            return result;
        }
    };