KAIST 산업및시스템공학과 문일철_ 데이터 구조 및 분석 수업을 참고하여 작성하였습니다

ch_3_6 Queue

Stack

1. Queue
    : A sceenario of a production line at a factory

2. Structure of Queue
    : linear like linked lists
        - A variation of singly linked list
    : Difference
        - Boluntarily giving up
          - Access to the middle in the linked list == Same to the stacks
          - Only accesses to the first and the last instances in the list
        - The first instance in the list
            = The front instance in the queue
        - The last instance in the list
            = The rear instance in the queue
        - An item is inserted at the last
        - An item is removed at the front
        - is called Fast-In-First-Out (FIFO)

3. Operation of Queue
    : Enqueue
        = Insert an instance at the last in the linked list
        = Put an instance at the rear in the queue
    : Dequeue
        = Remove and return an instance at the first in the linked list
        = Remove and return an instance at the front in the queue

4. Implementation of Queue
    : Python code of a queue
        - Utilizing a singly linked list (I retrieval count)
        - To dequeue an instance (I retrieval count)

from edu.kaist.seslab.ie362.week3.SinglyLinkedList import SinglyLinkedList

class Queue(object) :
    lstInstance = SinglyLinkedList()
    def Enqueue(self):
        return self.lstInstance.removeAt(0)
    def Dequeue(self):
        self.lstInstance.insertAt(value, self.lstInstance.geteSize())

queue =  Queue()
queue.enqueue('a')
queue.enqueue('b')
queue.enqueue('c')

print(queue.dequeue())
print(queue.dequeue())
print(queue.dequeue())

# a
# b
# c