Python数据结构 Dequeue
一个双端队列,或称 deque,支持从任何一端添加和删除元素。更常用的堆栈和队列是 deque 的退化形式,其中输入和输出被限制在一个端点上。
例子
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)
输出
当上述代码被执行时,它产生了以下结果 –
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'])