Intersection of Two Arrays - Leetcode 349 - Java

Program to calculate the intersection of two arrays returning only unique elements common to both arrays in any order. Explain the reasoning behind why HashSet will work. Solve the solution using two sets and also with one set. Problem: https://leetcode.com/problems/intersection-of-two-arrays/description/ Code link: https://k5kc.com/cs/problems/intersection-of-two-arrays-1-unique-elements/