32 lines
		
	
	
		
			859 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			32 lines
		
	
	
		
			859 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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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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| 
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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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| 
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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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| 
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| #### 示例用法
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| 
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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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|  
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|  queue.append("May") 
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|  
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|  queue.popleft() 
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|  queue.popleft() 
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|  
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|  print "Spring months in the list: ", queue 
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| ```
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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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| 
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| #### 更多信息:
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| 
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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 |