leetcode/algorithms/python/15_3Sum.py at master · tom721/leetcode · GitHub

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class Solution:
    def threeSum(self, nums: List[int]) -> List[List[int]]:
        answer = []
        nums.sort()
        for i in range(len(nums)-2):
            if i > 0 and nums[i] == nums[i-1]:
                continue
            left, right = i+1, len(nums)-1
            while left < right:
                three_sum = nums[i] + nums[left] + nums[right]
                if three_sum == 0:
                    answer.append([nums[i],nums[left],nums[right]])
                    while left < right and nums[left] == nums[left+1]:
                        left += 1
                    while left < right and nums[right] == nums[right-1]:
                        right -= 1
                    left += 1
                    right -= 1
                elif three_sum < 0:
                    left += 1
                else:
                    right -= 1
        return answer