022_generate-parantheses.py

class Solution(object):
    def generateParenthesis(self, n):
        """
        :type n: int
        :rtype: List[str]
        """
        parantheses = []
        def paranthesis(open, close, parenstring = ""):
            if close >= open:
                if open:
                    paranthesis(open - 1, close, parenstring + "(")
                if close:
                    paranthesis(open, close - 1, parenstring + ")")
                if open == close and open == 0:
                    print(parenstring)
                    parantheses.append(parenstring)
        paranthesis(n - 1, n, "(")

        return parantheses
print(Solution().generateParenthesis(2))
print(Solution().generateParenthesis(3))
print(Solution().generateParenthesis(4))