32 lines
859 B
Markdown
32 lines
859 B
Markdown
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---
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title: Deque
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localeTitle: 和
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---
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## 使用列表作为队列
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还可以使用列表作为队列，其中需要FIFO（“先进先出”）操作。列表效率不高 使用追加和弹出时的队列，因为它可能会变慢，因为每个追加/弹出都必须将所有元素移动一个。
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要实现队列，请使用collections.deque，它设计为具有快速追加和两端弹出。
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#### 示例用法
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```py
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from collections import deque
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queue = deque(["January", "February", "March", "April"] )
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queue.append("May")
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queue.popleft()
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queue.popleft()
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print "Spring months in the list: ", queue
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```
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#### 产量
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```
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Spring months in the list: deque(['March', 'April', 'May'])
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```
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#### 更多信息：
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`collections.deque`的官方文档可以在[这里](https://docs.python.org/3/library/collections.html#collections.deque)找到
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