Python Data Structure 简明教程

Python - Dequeue

双端队列或双向队列支持从任一端添加和移除元素。更为常用的堆栈和队列是双向队列的简化形式，其中输入和输出被限制在单个末端。

Example

import collections

DoubleEnded = collections.deque(["Mon","Tue","Wed"])
DoubleEnded.append("Thu")

print ("Appended at right - ")
print (DoubleEnded)

DoubleEnded.appendleft("Sun")
print ("Appended at right at left is - ")
print (DoubleEnded)

DoubleEnded.pop()
print ("Deleting from right - ")
print (DoubleEnded)

DoubleEnded.popleft()
print ("Deleting from left - ")
print (DoubleEnded)

Output

执行上述代码后，将生成以下结果 −

Appended at right -
deque(['Mon', 'Tue', 'Wed', 'Thu'])
Appended at right at left is -
deque(['Sun', 'Mon', 'Tue', 'Wed', 'Thu'])
Deleting from right -
deque(['Sun', 'Mon', 'Tue', 'Wed'])
Deleting from left -
deque(['Mon', 'Tue', 'Wed'])