35 lines
786 B
Python
35 lines
786 B
Python
class MinStack:
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def __init__(self):
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self.stack = []
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self.min_stack = []
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def push(self, val: int) -> None:
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self.stack.append(val)
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if not self.min_stack:
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self.min_stack.append(val)
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else:
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self.min_stack.append(min(val, self.min_stack[-1]))
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def pop(self) -> None:
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if self.min_stack:
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self.min_stack.pop()
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if self.stack:
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self.stack.pop()
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else:
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return None
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def top(self) -> int:
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return self.stack[-1]
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def getMin(self) -> int:
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if self.min_stack:
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return self.min_stack[-1]
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else:
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return None
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if __name__ == "__main__":
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s = MinStack()
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s.push(12)
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s.pop()
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s.pop()
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print(s.getMin())
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