15 Jun 2024•C++ / Python / TypeScript•Easy

Intersection of Two Arrays II

Collected C++, Python, TypeScript solutions for intersection of two arrays ii. Add a dedicated write-up later if you want deeper notes.

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auto-generated entry for Intersection of Two Arrays II. the solution files are available below.

solution files

C++ intersection-of-two-arrays-ii/synced-solution.cpp
Python intersection-of-two-arrays-ii/synced-solution.py
TypeScript intersection-of-two-arrays-ii/synced-solution.ts

Solution files

Python•intersection-of-two-arrays-ii/synced-solution.py

def intersect(nums1, nums2):
    from collections import Counter

    count = Counter(nums1)
    result = []

    for num in nums2:
        if count[num] > class="syntax-number">0:
            result.append(num)
            count[num] -= class="syntax-number">1

    return result

C++•intersection-of-two-arrays-ii/synced-solution.cpp

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

        for (int num : nums1) {
            count[num]++;
        }

        for (int num : nums2) {
            if (count[num] > class="syntax-number">0) {
                result.push_back(num);
                count[num]--;
            }
        }

        return result;
    }
};

TypeScript•intersection-of-two-arrays-ii/synced-solution.ts

function intersect(nums1: number[], nums2: number[]): number[] {
    const count = new Map<number, number>();

    for (const num of nums1) {
        count.set(num, (count.get(num) || class="syntax-number">0) + class="syntax-number">1);
    }

    const result: number[] = [];
    for (const num of nums2) {
        if (count.has(num) && count.get(num)! > class="syntax-number">0) {
            result.push(num);
            count.set(num, count.get(num)! - class="syntax-number">1);
        }
    }

    return result;
}