349. Intersection of Two Arrays

https://leetcode.com/problems/intersection-of-two-arrays

Python

class Solution:
    def intersection(self, nums1: List[int], nums2: List[int]) -> List[int]:
        return list(set(nums1) & set(nums2))

Go

func intersection(nums1 []int, nums2 []int) []int {
    // Covert nums2 into map, key as num2, value with true (whatever)
    nums2Map := map[int]bool{}
    for _, num2 := range nums2 {
        nums2Map[num2] = true
    }

    // If num1 in nums2, append to resultMap
    // Duplicate item will be overwrite
    resultMap := map[int]bool{}
    for _, num1 := range nums1 {
        if _, exist := nums2Map[num1]; exist {
            resultMap[num1] = true
        }
    }

    // Covert resultMap back to []int
    i := 0
    result := make([]int, len(resultMap))
    for num, _ := range resultMap {
        result[i] = num
        i++
    }

    return result
}