65 lines
1.2 KiB
Python
65 lines
1.2 KiB
Python
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# implemented by Linked list
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class Node(object):
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def __init__(self, item = None):
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self.item = item
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self.next = None
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self.previous = None
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class Queue(object):
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def __init__(self):
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self.length = 0
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self.head = None
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self.tail = None
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def enqueue(self, x):
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newNode = Node(x)
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if self.head == None:
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self.head = self.tail = newNode
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else:
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self.tail.next = newNode
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newNode.previous = self.tail
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self.tail = newNode
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self.length += 1
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def dequeue (self):
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item = self.head.item
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self.head = self.head.next
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self.length -= 1
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if self.length == 0:
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self.last = None
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return item
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#################################################
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# implemented by array
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class Queue:
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def __init__(self):
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self.items = []
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def is_empty(self):
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return self.items == []
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def enqueue(self, data):
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self.items.append(data)
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def dequeue(self):
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return self.items.pop(0)
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def display(self):
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ar = []
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for i in self.items:
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ar.append(i)
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return ar
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que = Queue()
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que.enqueue('google')
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que.enqueue('youtube')
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que.enqueue('udemy')
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que.enqueue('udacity')
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que.dequeue()
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que.dequeue()
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print(que.display())
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