35 lines
641 B
Python
35 lines
641 B
Python
s = "]"
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def isValid(s):
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open_list = ["(", "{", "["]
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close_list = [")", "}", "]"]
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stack=[]
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for i in range(0, len(s)):
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char = s[i]
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if char in open_list:
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stack.append(char)
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elif char in close_list:
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# find index of closing char
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index = close_list.index(char)
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matching_open_char = open_list[index]
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if stack and stack[-1]==matching_open_char:
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stack.pop()
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else:
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return False # in case str="]"
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if not stack:
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return True
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else:
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return False
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print isValid(s) |