349. Intersection of Two Arrays java solutions

 1 public class Solution {
 2     public int[] intersection(int[] nums1, int[] nums2) {
 3         int len1 = nums1.length, len2 = nums2.length;
 4         Set<Integer> set = new HashSet<Integer>();
 5         Set<Integer> set2 = new HashSet<Integer>();
 6         for(int i = 0; i < len1; i++){
 7             set.add(nums1[i]);
 8         }
 9         for(int i = 0; i < len2; i++){
10             if(set.contains(nums2[i])) set2.add(nums2[i]);
11         }
12         int[] res = new int[set2.size()];
13         int index = 0;
14         for(int ans : set2){
15             res[index++] = ans;
16         }
17         return res;
18     }
19 }