CODEWITHSUNDEEP
pythonqueue
Amidii
Amidii

Reputation: 355

python queue using embedded list

Write a class and implement a list using embedded python list.

Input like : 4 9 3 5

Output should be like: 3 4 5 9

I use this code for taking the input values and split it to the list

s = input()
numbers = map(int, s.split())

How can i build up a class for this listPQ that takes the lists values and put, get and check if the list is empty?

To try if your queue works:

   q = ListPQ()
   q.put(3)
   q.put(4)
   x = q.get()
   y = q.get()
   print(x,y)   #it should print 3 4

Upvotes: 1

Views: 260

Answers (2)

adarsh
adarsh

Reputation: 6978

class ListPQ():
    def __init__(self):
        self.pq = []

    def put(self, val):
        # Write code to put the number and keep it in sorted way, however you decide to
        # you can use self.pq to access the list and add stuff to it... this instance
        # of the class will have it saved.
        self.pq.append(val)
        self.pq.sort() # This is just for brevity, you can use your own algo for this

    def get(self):
        # likewise, use the self.pq to pop it out like,
        return self.pq.pop(-1)

    def is_empty(self):
        return len(self.pq) == 0

    def __repr__(self):
        return "<ListPQ: %r>" % self.pq

Now you can go ahead and use print(instance_of_listpq) and this will print out the list as it's written in the __repr__ method.

Hope this helps now!

Upvotes: 1

TobiMarg
TobiMarg

Reputation: 3797

You could use the heapq module from the python standard library. Then it is even possible without a class.

Without class:

import heapq
h = []
heapq.heappush(h, 4)
heapq.heappush(h, 3)
heapq.heappush(h, 9)
heapq.heappush(h, 5)
print(heapq.heappop(h))
print(heapq.heappop(h))
print(heapq.heappop(h))
print(heapq.heappop(h))

the output would be (space instead of newline):

3 4 9 5

If you need a class you can do it as follows:

class ListPQ():
    def __init__(self):
        self.h = []

    def put(self, item):
        heapq.heappush(self.h, item)

    def get(self):
        return heapq.heappop(self.h)

Upvotes: 0

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