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

/*
 * @lc app=leetcode.cn id=349 lang=java
 *
 * [349] 两个数组的交集
 */

// @lc code=start
class Intersection {
  public int[] intersection(int[] nums1, int[] nums2) {
    Set<Integer> set1 = new HashSet<>();
    Set<Integer> set2 = new HashSet<>();
    for (int num : nums1) {
      set1.add(num);
    }
    for (int num : nums2) {
      if (set1.contains(num)) {
        set2.add(num);
      }
    }
    int[] res = new int[set2.size()];
    int i = 0;
    for (Integer num : set2) {
      res[i] = num;
      i++;
    }
    return res;
  }
}
// @lc code=end