InterSectionOfTwoArrays.java

// 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.

import java.util.HashSet;
import java.util.Set;

class Solution {
    public int[] intersection(int[] nums1, int[] nums2) {
        Set<Integer> set = new HashSet<>();
        for (int i = 0; i < nums1.length; i++) {
            set.add(nums1[i]);
        }
        Set<Integer> set2 = new HashSet<>();
        for (int i = 0; i < nums2.length; i++) {
            if (set.contains(nums2[i])) {
                set2.add(nums2[i]);
            }
        }
        int[] res = new int[set2.size()];
        int i = 0;
        for (Integer num : set2) {
            res[i++] = num;
        }
        return res;
        
        
    }
}