/**

public static void main(String[] args) throws Exception {

int[] nums = {

-1, 0, 1, 2, -1, -4, -1, 0, 1, 2, -1, -4, -1, 0, 1, 2, -1, -4, -1, 0, 1, 2, -1, -4, -1, 0, 1,

2, -1, -4, -1, 0, 1, 2, -1, -4, -1, 0, 1, 2, -1, -4, -1, 0, 1, 2, -1, -4

};

System.out.println(new ThreeSum().threeSum(nums));

}

public List<List<Integer>> threeSum(int[] nums) {

List<List<Integer>> result = new ArrayList<>();

if (nums.length < 3) return result;

Arrays.sort(nums);

for (int i = 0, l = nums.length; i < l - 2; i++) {

if (i == 0 || nums[i] != nums[i - 1]) {

int j = i + 1, k = l - 1;

while (k > j) {

if (j != i + 1 && nums[j] == nums[j - 1]) {

j++;

continue;

}

int sum = nums[i] + nums[j] + nums[k];

if (sum == 0) {

result.add(Arrays.asList(nums[i], nums[j], nums[k]));

k--;

j++;

} else if (sum > 0) k--;

else j++;

}

}

}

return result;

}