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Simple Queue Implementation using Python

Stacks and Queues are not data structures, they are basically abstract data types. The simple data structure can be an array or a linked list.

Queues are FIFO.. First In and First Out.

Queues do have real world operations like:-
1.    Token System
2.    Organising data to archive based on age.
3.    Scheduling
4.    Any task which involves first come first serve basis.

Below is a simple implementation of Queue using Python.

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class Queue:

    def __init__(self):
        self.queue = []

    def isEmpty(self):
        return self.queue == []

    def enqueue(self, data):
        self.queue.append(data)

    def dequeue(self):
        data = self.queue[0]
        del self.queue[0]
        return data

    def peek(self):
        return self.queue[0]

    def sizeQueue(self):
        return len(self.queue)

    def dispQueue(self):
        for l in range(0,len(self.queue)):
            print ("Position {0} Element is {1}".format(l,self.queue[l]))

'''-------------------------- Main Code ------------------------------------'''
i = 0
numberOfElements =int(input("Enter number of Elements to enqueue to queue:        "))
userqueue = Queue()

for i in range(0, numberOfElements):
    number =int(input("Enter the {0} item number to enqueue to queue at first:        ".format(i)))
    userqueue.enqueue(number)

print("Size of queue is : {0} ".format(userqueue.sizeQueue()))
print("dequeue: ",userqueue.dequeue())

userqueue.dispQueue()




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