43 lines
1.2 KiB
Python
43 lines
1.2 KiB
Python
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class Solution:
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def isValid(self, s: str) -> bool:
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def rcg_type(ch) -> int:
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if ch[0] =='(':
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return 1
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if ch[0] ==')':
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return 2
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if ch[0] =='{':
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return 3
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if ch[0] =='}':
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return 4
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if ch[0] =='[':
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return 5
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if ch[0] ==']':
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return 6
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stack = []
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top_idx = -1
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def is_empty():
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return top_idx == -1
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def set_ele(stack: list, idx: int, ele: int):
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if len(stack) <= idx:
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stack.append(ele)
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else:
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stack[idx] = ele
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for ch in s:
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tp = rcg_type(ch)
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if tp % 2 == 1:
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top_idx += 1
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set_ele(stack, top_idx, tp)
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else:
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if is_empty(): return False
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top_ele = stack[top_idx]
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if tp - top_ele != 1: return False
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top_idx -= 1
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if not is_empty(): return False
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return True
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sol = Solution()
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print(sol.isValid("()"))
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print(sol.isValid("(){}[]"))
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print(sol.isValid("(]"))
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print(sol.isValid("[(])"))
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