31 lines
774 B
Python
31 lines
774 B
Python
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from collections import deque
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class Solution:
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bracket_pairing = {
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'{': '}',
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'[': ']',
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'(': ')'
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}
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closing_brackets = tuple(bracket_pairing.values())
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def is_matching_pair(self, opening, closing):
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return self.bracket_pairing[opening] == closing
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def isValid(self, s: str) -> bool:
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stack = deque()
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for c in s:
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if c in self.closing_brackets:
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try:
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last_char = stack.pop()
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except IndexError:
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return False
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if not self.is_matching_pair(last_char, c):
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return False
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else:
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stack.append(c)
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return len(stack) == 0
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