package Week_01; import java.util.HashSet; public class S1TwoSum { public static int[] twoSum(int[] nums, int target) { HashSet hashSet = new HashSet<>(); for (int num: nums) { hashSet.add(num); } for (int i = 0; i < nums.length; i++) { if (hashSet.contains(target - nums[i])) { for (int j = 0; j < nums.length; j++) { if (nums[j] == target - nums[i] && j != i) { System.out.println(i); System.out.println(j); return new int[]{i, j}; } } } } return null; } }