Data-Structures-and-Algorithms/Python/balanced_parentheses.py at main · codemistic/Data-Structures-and-Algorithms · GitHub

Name: Data-Structures-and-Algorithms/Python/balanced_parentheses.py at main · codemistic/Data-Structures-and-Algorithms · GitHub
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from .stackimportStack


defbalanced_parentheses(parentheses: str) ->bool:
"""Use a stack to check if a string of parentheses is balanced.
 >>> balanced_parentheses("([]{})")
 True
 >>> balanced_parentheses("[()]{}{[()()]()}")
 True
 >>> balanced_parentheses("[(])")
 False
 >>> balanced_parentheses("1+2*3-4")
 True
 >>> balanced_parentheses("")
 True
 """
stack: Stack[str] =Stack()
bracket_pairs= {"(": ")", "[": "]", "{": "}"}
forbracketinparentheses:
ifbracketinbracket_pairs:
stack.push(bracket)
elifbracketin (")", "]", "}"):
ifstack.is_empty() orbracket_pairs[stack.pop()] !=bracket:
returnFalse
returnstack.is_empty()


if__name__=="__main__":
fromdoctestimporttestmod

testmod()

examples= ["((()))", "((())", "(()))"]
print("Balanced parentheses demonstration:\n")
forexampleinexamples:
not_str=""ifbalanced_parentheses(example) else"not "
print(f"{example} is {not_str}balanced")