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Intersection of Two Arrays

Problem statement​

Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique and you may return the result in any order.

Example 1:

Input: nums1 = [1,2,2,1], nums2 = [2,2]Output: [2]

Example 2:

Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]Output: [9,4]Explanation: [4,9] is also accepted.

Constraints:

  • 1 <= nums1.length, nums2.length <= 1000
  • 0 <= nums1[i], nums2[i] <= 1000

My solution​

/**
 * @param {number[]} nums1
 * @param {number[]} nums2
 * @return {number[]}
 */
var intersection = function(nums1, nums2) {
    const memo = new Map()
    
    for (const num of nums1) {
        memo.set(num, (memo.get(num) || 0) + 1)
    }
    
    // console.log(memo)
    
    
    const result = []
    for (const num of nums2) {
        if (memo.get(num)) {
            result.push(num)
            memo.set(num, memo.get(num) - 1)
        }
    }
    
    return [...new Set(result)];
};