desnyki

public int findDuplicate(int[] nums) {
        if (nums.length > 1){
        int ptr1 = nums[0];
        int ptr2 = nums[nums[0]];
            
            while (ptr1 != ptr2)
		{
			ptr1 = nums[ptr1];
			ptr2 = nums[nums[ptr2]];
		}

desnyki

public List<List<Integer>> threeSum(int[] nums) {
        Arrays.sort(nums);
        Set<List<Integer>> result = new HashSet<List<Integer>>();
        Map<Integer, Integer> negC = new HashMap<>();

        for (int i = 0; i < nums.length; i++){
            negC.put(-nums[i], i);

        } 
        boolean flag = false;