Intersection of Two Arrays

class Solution {
public:
    vector<int> intersection(vector<int>& nums1, vector<int>& nums2) {
        unordered_set<int> set1(nums1.begin(), nums1.end());
        vector<int> ans;
        for (int v : nums2) {
            auto it = set1.find(v);
            if (it != set1.end()) { ans.push_back(v); set1.erase(it); }
        }
        return ans;
    }
};

func intersection(nums1 []int, nums2 []int) []int {
    set1 := make(map[int]bool, len(nums1))
    for _, v := range nums1 {
        set1[v] = true
    }
    ans := []int{}
    for _, v := range nums2 {
        if set1[v] {
            ans = append(ans, v)
            delete(set1, v)
        }
    }
    return ans
}

from typing import List

class Solution:
    def intersection(self, nums1: List[int], nums2: List[int]) -> List[int]:
        set1 = set(nums1)
        ans: List[int] = []
        for v in nums2:
            if v in set1:
                ans.append(v)
                set1.remove(v)
        return ans

function intersection(nums1, nums2) {
    const set1 = new Set(nums1);
    const ans = [];
    for (const v of nums2) {
        if (set1.has(v)) {
            ans.push(v);
            set1.delete(v);
        }
    }
    return ans;
}

class Solution {
    public int[] intersection(int[] nums1, int[] nums2) {
        Set<Integer> set1 = new HashSet<>();
        for (int v : nums1) set1.add(v);
        List<Integer> ans = new ArrayList<>();
        for (int v : nums2) {
            if (set1.remove(v)) ans.add(v);
        }
        int[] out = new int[ans.size()];
        for (int i = 0; i < ans.size(); i++) out[i] = ans.get(i);
        return out;
    }
}

function intersection(nums1: number[], nums2: number[]): number[] {
    const set1: Set<number> = new Set(nums1);
    const ans: number[] = [];
    for (const v of nums2) {
        if (set1.has(v)) {
            ans.push(v);
            set1.delete(v);
        }
    }
    return ans;
}