mathdatech/Python
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/Python.git synced 2025-02-07 01:50:55 +00:00
Code Issues Packages Projects Releases Wiki Activity

Update adaptive_merge_sort.py

Browse Source
This commit is contained in:
ANANT JAIN 2024-10-17 00:57:11 +05:30 committed by GitHub
parent 97aa418474
commit 8d5ecd6883
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 32 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
sorts/adaptive_merge_sort.py
View File

@ -1,39 +1,62 @@
def adaptive_merge_sort(sequence: list) -> list:
"""
Sorts a list using the Adaptive Merge Sort algorithm.
>>> adaptive_merge_sort([4, 3, 1, 2])
Initial sequence: [4, 3, 1, 2]
Sorting: array[0:2] and array[2:4]
Sorting: array[0:1] and array[1:2]
Sorting: array[2:3] and array[3:4]
Skipping merge as array[0] <= array[1]
Skipping merge as array[2] <= array[3]
Merging: array[0:2] and array[2:4]
After merge: [1, 2, 3, 4]
Sorted sequence: [1, 2, 3, 4]
[1, 2, 3, 4]
"""
if len(sequence) < 2:
return sequence
aux = sequence[:]
print(f"Initial sequence: {sequence}")
adaptive_merge_sort_helper(sequence, aux, 0, len(sequence) - 1)
print(f"Sorted sequence: {sequence}")
return sequence
def adaptive_merge_sort_helper(array: list, aux: list, low: int, high: int):
def adaptive_merge_sort_helper(array: list, aux: list, low: int, high: int) -> None:
"""
Helper function for Adaptive Merge Sort algorithm.
>>> adaptive_merge_sort_helper([4, 3, 1, 2], [4, 3, 1, 2], 0, 3)
Sorting: array[0:2] and array[2:4]
Sorting: array[0:1] and array[1:2]
Sorting: array[2:3] and array[3:4]
Skipping merge as array[0] <= array[1]
Skipping merge as array[2] <= array[3]
Merging: array[0:2] and array[2:4]
After merge: [1, 2, 3, 4]
"""
if high <= low:
return
mid = (low + high) // 2
print(f"Sorting: array[{low}:{mid + 1}] and array[{mid + 1}:{high + 1}]")
adaptive_merge_sort_helper(aux, array, low, mid)
adaptive_merge_sort_helper(aux, array, mid + 1, high)
if array[mid] <= array[mid + 1]:
print(f"Skipping merge as array[{mid}] <= array[{mid + 1}]")
array[low : high + 1] = aux[low : high + 1]
return
merge(array, aux, low, mid, high)
def merge(array: list, aux: list, low: int, mid: int, high: int) -> None:
"""
Merges two sorted subarrays of the main array.
def merge(array: list, aux: list, low: int, mid: int, high: int):
>>> merge([4, 3, 1, 2], [4, 3, 1, 2], 0, 1, 3)
Merging: array[0:2] and array[2:4]
After merge: [1, 2, 3, 4]
"""
print(f"Merging: array[{low}:{mid + 1}] and array[{mid + 1}:{high + 1}]")
i, j = low, mid + 1
for k in range(low, high + 1):
if i > mid:
aux[k] = array[j]
@ -47,5 +70,4 @@ def merge(array: list, aux: list, low: int, mid: int, high: int):
else:
aux[k] = array[i]
i += 1
print(f"After merge: {aux[low:high + 1]}")