Binary Heap Priority Queue


Keywords
binary-heap, priority-queue, python, python37
License
MIT
Install
pip install bhpq==2.0.1

Documentation

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BHPQ - Binary Heap Priority Queue

A binary heap priority queue implementation, thread safe

Installation

You can install bhpq from PyPI:

pip install bhpq

bhpq is supported on Python 3.7

Usage

from bhpq import BinaryHeapPriorityQueue

# The BinaryHeapPriorityQueue constructor takes two input params:

# - prefer (required param)
#    the preferred object is pushed to the top of the queue
# the prefer input is a lambda function eg:
# prefer=(lambda lhs, rhs: lhs if lhs.val >= rhs.val else rhs)

# - size
#    The initial size allocation of the queue, default value is 10

Example

class Node(object):
def __init__(self, val):
    self.val = val

A = BinaryHeapPriorityQueue(
        prefer=(lambda lhs, rhs: lhs if lhs.val >= rhs.val else rhs), size=5
    )

A.add(Node(1))
A.add(Node(4))
A.add(Node(3))
A.add(Node(5))
A.add(Node(2))

assert 5 == A.pop().val
assert 4 == A.pop().val
assert 3 == A.pop().val
assert 2 == A.pop().val
assert 1 == A.pop().val
assert None == A.pop()

Methods

  • size()

returns the current size of the priority queue

  • peek()

returns the object at the topof the priority queue if it exists else returns None

  • pop()

removes and returns the object at the top of the priority queue if it exists else returns None

  • add(val)

adds an element to the priority queue

Maintainer

Aayush Uppal