给你一个整数数组 nums ，判断是否存在三元组 [nums[i], nums[j], nums[k]] 满足 i != j、i != k 且 j != k ，同时还满足 nums[i] + nums[j] + nums[k] == 0 。请你返回所有和为 0 且不重复的三元组。

比官方三循环快1000ms的解法，57ms，击败91.37%

class Solution {
public:vector<vector<int>> threeSum(vector<int>& nums) {vector<vector<int>> result;int n = nums.size();sort(nums.begin(), nums.end());for (int i = 0; i < n - 2; ++i) {if (i == 0 || (i > 0 && nums[i] != nums[i-1])) {int target = -nums[i];int low = i + 1, high = n - 1;while (low < high) {if (nums[low] + nums[high] == target) {result.push_back({nums[i], nums[low], nums[high]});while (low < high && nums[low] == nums[low+1]) low++;while (low < high && nums[high] == nums[high-1]) high--;low++;high--;} else if (nums[low] + nums[high] < target) {low++;} else {high--;}}}}return result;}
};