67 lines
1.3 KiB
Python
67 lines
1.3 KiB
Python
from string import *
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from re import *
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from datetime import *
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from collections import *
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from heapq import *
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from bisect import *
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from copy import *
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from math import *
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from random import *
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from statistics import *
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from itertools import *
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from functools import *
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from operator import *
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from io import *
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from sys import *
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from json import *
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from builtins import *
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import string
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import re
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import datetime
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import collections
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import heapq
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import bisect
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import copy
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import math
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import random
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import statistics
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import itertools
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import functools
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import operator
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import io
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import sys
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import json
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from typing import *
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# @leet start
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class Solution:
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def generateParenthesis(self, n: int) -> List[str]:
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if n < 1:
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return []
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if n == 1:
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return ["()"]
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stack = []
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res = []
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def retrieveParenthesis(open, close):
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if open == close == n:
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res.append("".join(stack))
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return
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if open < n:
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stack.append('(')
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retrieveParenthesis(open + 1, close)
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stack.pop()
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if close < open:
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stack.append(')')
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retrieveParenthesis(open, close + 1)
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stack.pop()
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retrieveParenthesis(0, 0)
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return res
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# @leet end
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