leetcode 349. Intersection of Two Arrays

public class Solution { public int[] intersection(int[] nums1, int[] nums2) { Set<Integer> s1 = new HashSet<Integer>(); Set<Integer> s2 = new HashSet<Integer>(); for (int i: nums1) s1.add(Integer.valueOf(i)); for (int i: nums2) s2.add(Integer.valueOf(i)); s1.retainAll(s2); int[] res = new int[s1.size()]; int idx = 0; Iterator<Integer> iter = s1.iterator(); while(iter.hasNext()) res[idx++] = iter.next(); return res; } }