题解 | #三数之和#

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param num int整型一维数组 
# @return int整型二维数组
#
class Solution:
    def threeSum(self , num: List[int]) -> List[List[int]]:
        # write code here
        num.sort()
        res = []
        if len(num)<3:
            return []
        else:
            for i in range(len(num)):
                a = num[i]
                start = i+1
                end = len(num)-1
                while start < end:
                    cur = a + num[start] + num[end]
                    if cur == 0:
                        t = tuple([a,num[start],num[end]])
                        res.append(t)
                        res = list(set(res))
                        if a + num[start] + num[end] == 0 and start < end:
                            start += 1
                    if cur < 0:
                        start += 1
                    if cur > 0:
                        end += -1
            res.sort()
            return res