Python/sorts/tim_sort.py

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Python
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def binary_search(lst, item, start, end):
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if start == end:
return start if lst[start] > item else start + 1
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if start > end:
return start
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mid = (start + end) // 2
if lst[mid] < item:
return binary_search(lst, item, mid + 1, end)
elif lst[mid] > item:
return binary_search(lst, item, start, mid - 1)
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else:
return mid
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def insertion_sort(lst):
length = len(lst)
for index in range(1, length):
value = lst[index]
pos = binary_search(lst, value, 0, index - 1)
lst = lst[:pos] + [value] + lst[pos:index] + lst[index + 1 :]
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return lst
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def merge(left, right):
if not left:
return right
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if not right:
return left
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if left[0] < right[0]:
return [left[0], *merge(left[1:], right)]
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return [right[0], *merge(left, right[1:])]
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def tim_sort(lst):
"""
>>> tim_sort("Python")
['P', 'h', 'n', 'o', 't', 'y']
>>> tim_sort((1.1, 1, 0, -1, -1.1))
[-1.1, -1, 0, 1, 1.1]
>>> tim_sort(list(reversed(list(range(7)))))
[0, 1, 2, 3, 4, 5, 6]
>>> tim_sort([3, 2, 1]) == insertion_sort([3, 2, 1])
True
>>> tim_sort([3, 2, 1]) == sorted([3, 2, 1])
True
"""
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length = len(lst)
runs, sorted_runs = [], []
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new_run = [lst[0]]
sorted_array = []
i = 1
while i < length:
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if lst[i] < lst[i - 1]:
runs.append(new_run)
new_run = [lst[i]]
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else:
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new_run.append(lst[i])
i += 1
runs.append(new_run)
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for run in runs:
sorted_runs.append(insertion_sort(run))
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for run in sorted_runs:
sorted_array = merge(sorted_array, run)
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return sorted_array
def main():
lst = [5, 9, 10, 3, -4, 5, 178, 92, 46, -18, 0, 7]
sorted_lst = tim_sort(lst)
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print(sorted_lst)
if __name__ == "__main__":
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main()