Python – Queue.LIFOQueue 与 Collections.Deque

LIFOQueue和Deque都可以使用Python中的内置模块Queue和Collections使用，它们都是数据结构并且被广泛使用，但用途不同。在本文中，我们将考虑Queue.LIFOQueue和Collections.Deque在Python中的可用性、执行时间、工作、实现等方面的区别。

queue.LifoQueue：模块队列提供了一个 LIFO 队列，它在技术上用作堆栈。它通常用于同一进程中不同线程之间的通信。

下面是一个描述Lifo.Queue实现的程序：

Python3

# Import required module
import queue
 
# Initialize LIFO Queue
LIFOq = queue.LifoQueue(maxsize=3)
 
# qsize() give the maxsize of
# the Queue
print(LIFOq.qsize())
 
# Data Inserted as 5->9->1->7,
# same as Queue
LIFOq.put(1)
LIFOq.put(2)
LIFOq.put(3)
 
# Displaying if the Queue is full
print("Full: ", LIFOq.full())
 
# Displaying size of queue
print("Size: ", LIFOq.qsize())
 
# Data will be accessed in the
# reverse order Reverse of that
# of Queue
print(LIFOq.get())
print(LIFOq.get())
print(LIFOq.get())
 
# Displaying if the queue is empty or not
print("Empty: ", LIFOq.empty())

输出：

0
Full:  True
Size:  3
3
2
1
Empty:  True

collections.deque： Python中的 Deque（双端队列）是使用模块collections实现的。该数据结构主要用于队列。 FIFO 队列机制由append()和popleft()实现。与列表相比，它的操作要快得多。

下面是一个程序，说明了collections.deque的实现：

蟒蛇3

# Import required modules
import collections
 
# Initialize deque
Deque = collections.deque([10, 20, 30])
 
# Using append() to insert element at right end
# Inserts 0 at the end of deque
Deque.append(0)
 
# Printing modified deque
print("The deque after appending at right is:", Deque)
 
# Using appendleft() to insert element at left end
# Inserts 100 at the beginning of deque
Deque.appendleft(100)
 
# Printing modified deque
print("The deque after appending at left is: ", Deque)
 
 
# Using pop() to delete element from right end
# Deletes 0 from the right end of deque
Deque.pop()
 
# Printing modified deque
print("The deque after deleting from right is:", Deque);
 
# Using popleft() to delete element from left end
# Deletes 100 from the left end of deque
Deque.popleft()
 
# Printing modified deque
print("Queue:", Deque)

输出：

The deque after appending at right is: deque([10, 20, 30, 0])
The deque after appending at left is:  deque([100, 10, 20, 30, 0])
The deque after deleting from right is: deque([100, 10, 20, 30])
Queue: deque([10, 20, 30])

LIFOQueue 和 Deque 的区别：

Sr. no.	LIFO Queue	Dequeue
1	It implements stacks	It implements a double-edged queue
2	Present in Queue module	Present in Collections module
3	Allows various threads to communicate using queued data or messages	Simply intended to be a data structure
4	Fewer features (operations and methods)	Large Variety of features (operations and methods)
5	Follows Last In First Out	Follows First In First Out
6	Slow operations (long execution time)	High operations(very low execution time)
6	Not commonly used, usually used for thread communication operations.	Mostly used for data structure operations.