CPSC 386 example of how to use the Python heapq library

cpsc386_heap_thoughts.py

#!/usr/bin/env python3
# Gist: https://gist.github.com/mshafae/e8f2c047f5e43550b919ac2b5fc3dc5e
#
"Examples of how to work with Python's heap library"

from collections import namedtuple
from random import randint
import heapq
import pprint
import sys

def main():
    if sys.version_info > (3, 13):
        print('The heapq library now has heapq.heapify_max()')
        print('See https://docs.python.org/3/library/heapq.html')


    TTTMove = namedtuple('TTTMove', ['priority', 'junk'])

    # The priority is set to a negative number so we get max_heap behavior
    # from Python's min_heap. Ubuntu 24 uses Python 3.12 so we can't use 
    # the new heapify_max().
    move_list = [TTTMove((randint(1, 100)) * -1, 'foo') for _ in range(5)]

    print('Initial state of the list')
    pprint.pprint(move_list)

    # Heapify the list; remember heaps are actually trees
    heapq.heapify(move_list)

    print("Heapified:")
    pprint.pprint(move_list)

    n = heapq.heappop(move_list)
    print('Popped')
    pprint.pprint(n)

    print('List state')
    pprint.pprint(move_list)

    print('Push')
    heapq.heappush(move_list, TTTMove((randint(1, 1000)) * -1, 'foo'))

    print('List state')
    pprint.pprint(move_list)

    n = heapq.heappop(move_list)
    print('Popped')
    pprint.pprint(n)

    print('List state')
    pprint.pprint(move_list)

    print('Push')
    heapq.heappush(move_list, TTTMove((randint(1, 100)) * -1, 'foo'))

    print('List state')
    pprint.pprint(move_list)

    n = heapq.heappop(move_list)
    print('Popped')
    pprint.pprint(n)

if __name__ == '__main__':
    main()