Python: Create a heapsort, pushing all values onto a heap and then popping off the smallest values one at a time

Last update on April 23 2025 12:52:41 (UTC/GMT +8 hours)

24. Heapsort via Heap Operations

Write a Python program to create a heapsort, pushing all values onto a heap and then popping off the smallest values one at a time.

Sample Solution:

Python Code:

import heapq
def heapsort(h):
    heap = []
    for value in h:
        heapq.heappush(heap, value)
    return [heapq.heappop(heap) for i in range(len(heap))]

print(heapsort([10, 20, 50, 70, 90, 20, 50, 40, 60, 80, 100]))

Sample Output:

[10, 20, 20, 40, 50, 50, 60, 70, 80, 90, 100]

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to implement heapsort by first pushing all values onto a heap and then repeatedly popping the smallest element to form a sorted list.
• Write a Python script to demonstrate heapsort using heapq by converting a list to a heap and then extracting all elements in order.
• Write a Python program to sort a list using heap operations and print both the original and the sorted list.
• Write a Python function to perform heapsort on a list of integers and then compare the result with the output of Python’s built-in sorted() function.

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• Python Heap Queue Algorithm Exercises Home ↩
• Python Exercises Home ↩

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