二十五岁时我们都一样愚蠢、多愁善感，喜欢故弄玄虚，可如果不那样的话，五十岁时也就不会如此明智。
标题：Python - Deque
双端队列（deque）具有从任一端添加和删除元素的功能。Deque模块是集合库的一部分。它具有添加和删除可以直接用参数调用的元素的方法。在下面的程序中，我们导入集合模块并声明一个双端队列。不需要任何类，我们直接使用内置的实现这些方法。
import collections # Create a deque DoubleEnded = collections.deque(["Mon","Tue","Wed"]) print (DoubleEnded) # Append to the right print("Adding to the right: ") DoubleEnded.append("Thu") print (DoubleEnded) # append to the left print("Adding to the left: ") DoubleEnded.appendleft("Sun") print (DoubleEnded) # Remove from the right print("Removing from the right: ") DoubleEnded.pop() print (DoubleEnded) # Remove from the left print("Removing from the left: ") DoubleEnded.popleft() print (DoubleEnded) # Reverse the dequeue print("Reversing the deque: ") DoubleEnded.reverse() print (DoubleEnded)当上面的代码被执行时，它会产生以下结果：
deque(['Mon', 'Tue', 'Wed']) Adding to the right: deque(['Mon', 'Tue', 'Wed', 'Thu']) Adding to the left: deque(['Sun', 'Mon', 'Tue', 'Wed', 'Thu']) Removing from the right: deque(['Sun', 'Mon', 'Tue', 'Wed']) Removing from the left: deque(['Mon', 'Tue', 'Wed']) Reversing the deque: deque(['Wed', 'Tue', 'Mon'])
