mathdatech/Python
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/Python.git synced 2025-01-18 00:07:00 +00:00
Code Issues Packages Projects Releases Wiki Activity

doctest all_combinations.py (#12506)

Browse Source 
* doctest in all_combinations.py

* added doctest in all_combinations.py

* doctests in all_combinations.py

* add doctest all_combinations.py

* add

---------

Co-authored-by: Siddhant Jain <sjain35@buffalo.edu>
This commit is contained in:
Siddhant 2025-01-12 20:54:23 -05:00 committed by GitHub
parent 4c92de5e03
commit 787aa5d3b5
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 34 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
backtracking/all_combinations.py
View File

@ -12,6 +12,8 @@ from itertools import combinations
def combination_lists(n: int, k: int) -> list[list[int]]:
"""
Generates all possible combinations of k numbers out of 1 ... n using itertools.
>>> combination_lists(n=4, k=2)
[[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
"""
@ -20,6 +22,8 @@ def combination_lists(n: int, k: int) -> list[list[int]]:
def generate_all_combinations(n: int, k: int) -> list[list[int]]:
"""
Generates all possible combinations of k numbers out of 1 ... n using backtracking.
>>> generate_all_combinations(n=4, k=2)
[[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
>>> generate_all_combinations(n=0, k=0)
@ -34,6 +38,14 @@ def generate_all_combinations(n: int, k: int) -> list[list[int]]:
ValueError: n must not be negative
>>> generate_all_combinations(n=5, k=4)
[[1, 2, 3, 4], [1, 2, 3, 5], [1, 2, 4, 5], [1, 3, 4, 5], [2, 3, 4, 5]]
>>> generate_all_combinations(n=3, k=3)
[[1, 2, 3]]
>>> generate_all_combinations(n=3, k=1)
[[1], [2], [3]]
>>> generate_all_combinations(n=1, k=0)
[[]]
>>> generate_all_combinations(n=1, k=1)
[[1]]
>>> from itertools import combinations
>>> all(generate_all_combinations(n, k) == combination_lists(n, k)
... for n in range(1, 6) for k in range(1, 6))
@ -56,6 +68,28 @@ def create_all_state(
current_list: list[int],
total_list: list[list[int]],
) -> None:
"""
Helper function to recursively build all combinations.
>>> create_all_state(1, 4, 2, [], result := [])
>>> result
[[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
>>> create_all_state(1, 3, 3, [], result := [])
>>> result
[[1, 2, 3]]
>>> create_all_state(2, 2, 1, [1], result := [])
>>> result
[[1, 2]]
>>> create_all_state(1, 0, 0, [], result := [])
>>> result
[[]]
>>> create_all_state(1, 4, 0, [1, 2], result := [])
>>> result
[[1, 2]]
>>> create_all_state(5, 4, 2, [1, 2], result := [])
>>> result
[]
"""
if level == 0:
total_list.append(current_list[:])
return