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* Add the intial translation of code of all the languages * test * revert * Remove * Add Python and Java code for EN version
72 lines
2.0 KiB
Python
72 lines
2.0 KiB
Python
"""
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File: heap.py
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Created Time: 2023-02-23
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Author: krahets (krahets@163.com)
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"""
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import sys
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from pathlib import Path
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sys.path.append(str(Path(__file__).parent.parent))
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from modules import print_heap
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import heapq
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def test_push(heap: list, val: int, flag: int = 1):
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heapq.heappush(heap, flag * val) # Push the element into heap
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print(f"\nElement {val} after pushed into heap")
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print_heap([flag * val for val in heap])
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def test_pop(heap: list, flag: int = 1):
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val = flag * heapq.heappop(heap) # Pop the element at the heap top
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print(f"\nHeap top element {val} after exiting heap")
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print_heap([flag * val for val in heap])
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"""Driver Code"""
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if __name__ == "__main__":
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# Initialize min-heap
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min_heap, flag = [], 1
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# Initialize max-heap
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max_heap, flag = [], -1
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print("\nThe following test case is for max-heap")
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# Python's heapq module implements min-heap by default
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# Consider "negating the elements" before entering the heap, thus reversing the comparator to implement a max-heap
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# In this example, flag = 1 corresponds to min-heap, flag = -1 corresponds to max-heap
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# Push the element into heap
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test_push(max_heap, 1, flag)
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test_push(max_heap, 3, flag)
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test_push(max_heap, 2, flag)
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test_push(max_heap, 5, flag)
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test_push(max_heap, 4, flag)
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# Access heap top element
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peek: int = flag * max_heap[0]
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print(f"\nHeap top element is {peek}")
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# Pop the element at the heap top
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test_pop(max_heap, flag)
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test_pop(max_heap, flag)
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test_pop(max_heap, flag)
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test_pop(max_heap, flag)
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test_pop(max_heap, flag)
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# Get heap size
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size: int = len(max_heap)
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print(f"\nNumber of heap elements is {size}")
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# Determine if heap is empty
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is_empty: bool = not max_heap
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print(f"\nIs the heap empty {is_empty}")
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# Enter list and build heap
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# Time complexity is O(n), not O(nlogn)
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min_heap = [1, 3, 2, 5, 4]
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heapq.heapify(min_heap)
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print("\nEnter list and build min-heap")
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print_heap(min_heap)
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