Three Summedium

import java.util.*;

public class Main {
    public static List<List<Integer>> threeSum(int[] nums) {
        // TODO: find all unique triplets that sum to zero
        return new ArrayList<>();
    }

    public static void main(String[] args) {
        System.out.println(threeSum(new int[]{-1, 0, 1, 2, -1, -4}));
        System.out.println(threeSum(new int[]{0, 0, 0}));
    }
}