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# Copyright 2015 Egor Tensin <Egor.Tensin@gmail.com>
# This file is licensed under the terms of the MIT License.
# See LICENSE.txt for details.
# Disclaimer: implemented in the most literate way.
def heapsort(xs):
heapify(xs)
first, last = 0, len(xs) - 1
for end in range(last, first, -1):
xs[end], xs[first] = xs[first], xs[end]
siftdown(xs, first, end - 1)
return xs
# In a heap stored in a zero-based array,
# left_child = node * 2 + 1
# right_child = node * 2 + 2
# parent = (node - 1) // 2
def _get_parent(node):
return (node - 1) // 2
def _get_left_child(node):
return node * 2 + 1
def _get_right_child(node):
return node * 2 + 2
def heapify(xs):
last = len(xs) - 1
first_parent, last_parent = 0, _get_parent(last)
for parent in range(last_parent, first_parent - 1, -1):
siftdown(xs, parent, last)
def siftdown(xs, start, end):
root = start
while True:
# We swap if there is at least one child
child = _get_left_child(root)
if child > end:
break
# If there are two children, select the minimum
right_child = _get_right_child(root)
if right_child <= end and xs[child] < xs[right_child]:
child = right_child
if xs[root] < xs[child]:
xs[root], xs[child] = xs[child], xs[root]
root = child
else:
break
if __name__ == '__main__':
import sys
print(heapsort(list(map(int, sys.argv[1:]))))
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