题目:
代码(首刷看解析 2024年1月15日):
class Solution {
public:vector<vector<int>> fourSum(vector<int>& nums, int target) {vector<vector<int>> result;sort(nums.begin(), nums.end());for (int i = 0; i < nums.size(); i++) {if (nums[i] > target && nums[i] >= 0) {break; }if (i > 0 && nums[i] == nums[i - 1]) {continue;}for (int j = i + 1; j < nums.size(); j++) {if (nums[i] + nums[j] > target && nums[i] + nums[j] >= 0) {break;}if (j > i + 1 && nums[j] == nums[j - 1]) {continue;}int left = j + 1;int right = nums.size() - 1;while (right > left) {if ((long)nums[i] + nums[j] + nums[left] + nums[right] > target) {right--;}else if ((long)nums[i] + nums[j] + nums[left] + nums[right] < target) {left++;}else {result.push_back({nums[i], nums[j], nums[left], nums[right]});while (right > left && nums[right] == nums[right - 1]) right--;while (right > left && nums[left] == nums[left + 1]) left++;right--;left++;}}}}return result;}
};
不行了,今天做了太多n数之和要吐了,太恶心了,一堆剪枝,去重太恶心人了。最后还是照着卡哥的改