70 lines
1.0 KiB
Markdown
70 lines
1.0 KiB
Markdown
---
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title: leetcode-225
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date: 2020-03-23 23:35:05
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tags:
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categories: leetcode
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---
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### 225. 用队列实现栈
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[题目](https://leetcode-cn.com/problems/implement-stack-using-queues/)
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<!--more-->
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注意栈是 FILO(First In Last Out)，Python 的 list 是 FIFO(First In First Out)。
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```python
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class MyStack:
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def __init__(self):
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"""
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Initialize your data structure here.
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"""
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self.data = []
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def push(self, x: int) -> None:
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"""
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Push element x onto stack.
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"""
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self.data.append(x)
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return
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def pop(self) -> int:
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"""
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Removes the element on top of the stack and returns that element.
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"""
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return self.data.pop(-1)
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def top(self) -> int:
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"""
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Get the top element.
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"""
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return self.data[-1]
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def empty(self) -> bool:
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"""
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Returns whether the stack is empty.
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"""
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return not bool(self.data)
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# Your MyStack object will be instantiated and called as such:
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# obj = MyStack()
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# obj.push(x)
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# param_2 = obj.pop()
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# param_3 = obj.top()
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# param_4 = obj.empty()
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#24 ms 13.5 MB
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```
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