5元一条，加个条件，输出括号的数量即可

Question

class Solution:
def generateParenthesis(self, n):
"""
:type n: int
:rtype: List[str]
"""
out_list = []
self.recrusion('', out_list, n, n)
return out_list

def recrusion(self, s, out_list, left, right):
    if left == right == 0:
        out_list.append(s)
    if left > 0:
        self.recrusion(s+'(', out_list, left-1, right)
    if right > left:
        self.recrusion(s+')', out_list, left, right-1)

if name == 'main':
print()
s1 = Solution()
print(s1.generateParenthesis(4))

Answer 1

你这个不就是看指定对数的括号，有多少种排列了吗？你要输出什么？