mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-10-06 05:39:30 +00:00
93fb555e0a
* Enable ruff SIM102 rule * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci * Fix * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
39 lines
1.1 KiB
Python
39 lines
1.1 KiB
Python
from .stack import Stack
|
|
|
|
|
|
def balanced_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 = {"(": ")", "[": "]", "{": "}"}
|
|
for bracket in parentheses:
|
|
if bracket in bracket_pairs:
|
|
stack.push(bracket)
|
|
elif bracket in (")", "]", "}") and (
|
|
stack.is_empty() or bracket_pairs[stack.pop()] != bracket
|
|
):
|
|
return False
|
|
return stack.is_empty()
|
|
|
|
|
|
if __name__ == "__main__":
|
|
from doctest import testmod
|
|
|
|
testmod()
|
|
|
|
examples = ["((()))", "((())", "(()))"]
|
|
print("Balanced parentheses demonstration:\n")
|
|
for example in examples:
|
|
not_str = "" if balanced_parentheses(example) else "not "
|
|
print(f"{example} is {not_str}balanced")
|