15. 3Sum

Python

class Solution:#시간초과로 오래 걸림
    def threeSum(self, nums: List[int]) -> List[List[int]]:
        answer = []
        set_answer = set()
        nums.sort()
        j = 1
        i = 0
        k = 2
        if len(nums) < 3:
            return answer
        
        for i in range(len(nums[:-2])):
            j, k = i + 1, len(nums) - 1
            while True:
                if j >= k:
                    break
                total = nums[i] + nums[j] + nums[k]
                if total == 0:
                    if (nums[i], nums[j], nums[k]) not in set_answer:
                        set_answer.add((nums[i], nums[j], nums[k]))
                        answer.append([nums[i], nums[j], nums[k]])
                    j += 1
                    k -=1
                if total > 0:
                    k -= 1
                elif total < 0:
                    j += 1
                    

        return answer