Python - 数据结构之出队

  • 简述

    双端队列或双端队列支持从任一端添加和删除元素。更常用的堆栈和队列是双端队列的退化形式,其中输入和输出被限制在一个端。
  • 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

    执行上述代码时,会产生以下结果 -
    
    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'])