def heapsort(arr):
"""
:description: heapsort, version not in place b/c the heap ops don't take heap size parameter. Works by removing largest element and calling max_heapify
:time: O(nlgn) worst case calls max_heapify n times
:space: O(n)
"""
heap = arr
heap_ops.build_max_heap(heap)
sorted_arr = []
for i in range(len(arr) - 1):
heap[0], heap[-1] = heap[-1], heap[0]
sorted_arr.append(heap.pop())
heap_ops.max_heapify(heap, 0)
sorted_arr.append(heap.pop())
return list(reversed(sorted_arr))
def heapsort(arr):
"""
:description: heapsort, version not in place b/c the heap ops don't take heap size parameter. Works by removing largest element and calling max_heapify
:time: O(nlgn) worst case calls max_heapify n times
:space: O(n)
"""
heap = arr
heap_ops.build_max_heap(heap)
sorted_arr = []
for i in range(len(arr) - 1):
heap[0], heap[-1] = heap[-1], heap[0]
sorted_arr.append(heap.pop())
heap_ops.max_heapify(heap, 0)
sorted_arr.append(heap.pop())
return list(reversed(sorted_arr))
"""
heap_increase_key(heap, i, heap_max(heap) + 1)
heap_extract_max(heap)
def max_heap_insert(heap, value):
"""
:description: insert an element into the heap
:time: O(lgn)
"""
heap.append(-sys.maxint)
heap_increase_key(heap, len(heap) - 1, value)
if __name__ =='__main__':
data = [1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,5,4,3,2,1,2,3,4,5]
heap_ops.build_max_heap(data)
result = heap_max(data) == max(data)
print 'correct?: {}'.format(result)
data = [1,2,3]
heap_ops.build_max_heap(data)
max_value = heap_extract_max(data)
result = max_value == 3
print 'correct?: {}'.format(result)
result = data == [2,1]
print 'correct?: {}'.format(result)
data = [1,2,3]
heap_ops.build_max_heap(data)
heap_increase_key(data, 2, 10)
result = data == [10, 2, 3] or data == [10, 3, 2]
def max_heap_insert(heap, value):
"""
:description: insert an element into the heap
:time: O(lgn)
"""
heap.append(-sys.maxint)
heap_increase_key(heap, len(heap) - 1, value)
if __name__ == '__main__':
data = [
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 2, 3,
4, 5
]
heap_ops.build_max_heap(data)
result = heap_max(data) == max(data)
print 'correct?: {}'.format(result)
data = [1, 2, 3]
heap_ops.build_max_heap(data)
max_value = heap_extract_max(data)
result = max_value == 3
print 'correct?: {}'.format(result)
result = data == [2, 1]
print 'correct?: {}'.format(result)
data = [1, 2, 3]
heap_ops.build_max_heap(data)
heap_increase_key(data, 2, 10)
result = data == [10, 2, 3] or data == [10, 3, 2]
