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Neha Kumawat
2 years ago
class Queue:
def __init__(self):
self.queue = list()
def addtoq(self,dataval):
# Insert method to add element
if dataval not in self.queue:
self.queue.insert(0,dataval)
return true
return false
def size(self):
return len(self.queue)
TheQueue = Queue()
TheQueue.addtoq("JAN")
TheQueue.addtoq("FEB")
TheQueue.addtoq("MARCH")
print(TheQueue.size())
3
class Queue:
def __init__(self):
self.queue = list()
def addtoq(self,dataval):
# Insert method to add element
if dataval not in self.queue:
self.queue.insert(0,dataval)
return true
return false
# Pop method to remove element
def removefromq(self):
if len(self.queue)>0:
return self.queue.pop()
return ("No elements in Queue!")
q = Queue()
q.addtoq("JAN")
q.addtoq("FEB")
q.addtoq("Wed")
print(q.removefromq())
print(q.removefromq())
JAN
FEB
# Python program to
# demonstrate queue implementation
# using list
# Initializing a queue
q = []
# Adding elements to the queue
q.append('a')
q.append('b')
q.append('c')
print("Initial queue")
print(q)
# Removing elements from the queue
print("\nElements dequeued from queue")
print(q.pop(0))
print(q.pop(0))
print(q.pop(0))
print("\nQueue after removing elements")
print(q)
# Uncommenting print(q.pop(0))
# will raise and IndexError
# as the queue is now empty
Initial queue
['a', 'b', 'c']
Elements dequeued from queue
a
b
c
Queue after removing elements
[]
Traceback (most recent call last):
File "/home/ef51acf025182ccd69d906e58f17b6de.py", line 25, in
print(queue.pop(0))
IndexError: pop from empty list
# Python program to
# demonstrate queue implementation
# using collections.dequeue
from collections import deque
# Initializing a queue
queue = deque()
# Adding elements to a queue
queue.append('a')
queue.append('b')
queue.append('c')
print("Initial queue")
print(queue)
# Removing elements from a queue
print("\nElements dequeued from the queue")
print(queue.popleft())
print(queue.popleft())
print(queue.popleft())
print("\nQueue after removing elements")
print(queue)
# Uncommenting queue.popleft()
# will raise an IndexError
# as queue is now empty
Initial queue
deque(['a', 'b', 'c'])
Elements dequeued from the queue
a
b
c
Queue after removing elements
deque([])
Traceback (most recent call last):
File "/home/b2fa8ce438c2a9f82d6c3e5da587490f.py", line 23, in
q.popleft()
IndexError: pop from an empty deque
# Python program to
# demonstrate implementation of
# queue using queue module
from queue import Queue
# Initializing a queue
queue = Queue(maxsize = 3)
# qsize() give the maxsize
# of the Queue
print(queue.qsize())
# Adding of element to queue
queue.put('x')
queue.put('y')
queue.put('z')
# Return Boolean for Full
# Queue
print("\nFull: ", queue.full())
# Removing element from queue
print("\nElements dequeued from the queue")
print(queue.get())
print(queue.get())
print(queue.get())
# Return Boolean for Empty
# Queue
print("\nEmpty: ", queue.empty())
queue.put(1)
print("\nEmpty: ", queue.empty())
print("Full: ", queue.full())
# This would result in Infinite
# Loop as the Queue is empty.
# print(queue.get())
0
Full: true
Elements dequeued from the queue
x
y
z
Empty: true
Empty: false
Full: false
class Node:
def __init__(self,data):
self.data=data
self.next=None
class Queue:
def __init__(self):
self.front=None
self.queueSize=0
def enQueue(self,data):
temp=Node(data)
if self.front is None:
self.front=temp
self.queueSize= self.queueSize+1
else:
curr=self.front
while curr.next!=None:
curr=curr.next
curr.next=temp
self.queueSize=self.queueSize+1
def deQueue(self):
try:
if self.front == None:
raise Exception("Queue is Empty")
else:
temp=self.front
self.front=self.front.next
tempdata=temp.data
self.queueSize= self.queueSize-1
del temp
return tempdata
except Exception as e:
print(str(e))
def front_element(self):
try:
if self.front == None:
raise Exception("Queue is Empty")
else:
return self.front.data
except Exception as e:
print(str(e))
def size(self):
return self.queueSize
def isEmpty(self):
if self.queueSize==0:
return True
else:
return False