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[pre-commit.ci] auto fixes from pre-commit.com hooks

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pre-commit-ci[bot] 2024-10-14 15:32:46 +00:00
parent 991a37e9ff
commit d286529fdc
2 changed files with 49 additions and 26 deletions
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60
graphs/edmonds_blossom_algorithm.py
View File

@ -2,8 +2,15 @@ from collections import deque
class BlossomAuxData:
def __init__(self, queue: deque, parent: list[int], base: list[int],
in_blossom: list[bool], match: list[int], in_queue: list[bool]):
def __init__(
self,
queue: deque,
parent: list[int],
base: list[int],
in_blossom: list[bool],
match: list[int],
in_queue: list[bool],
):
self.queue = queue
self.parent = parent
self.base = base
@ -11,6 +18,7 @@ class BlossomAuxData:
self.match = match
self.in_queue = in_queue
class BlossomData:
def __init__(self, aux_data: BlossomAuxData, u: int, v: int, lca: int):
self.aux_data = aux_data
@ -18,6 +26,7 @@ class BlossomData:
self.v = v
self.lca = lca
class EdmondsBlossomAlgorithm:
UNMATCHED = -1 # Constant to represent unmatched vertices
@ -72,8 +81,11 @@ class EdmondsBlossomAlgorithm:
parent[y] = current
augmenting_path_found = True
# Augment along this path
(EdmondsBlossomAlgorithm
.update_matching(match, parent, y))
(
EdmondsBlossomAlgorithm.update_matching(
match, parent, y
)
)
break
# Case 2: y is matched, add y's match to the queue
@ -86,17 +98,25 @@ class EdmondsBlossomAlgorithm:
else:
# Case 3: Both current and y have a parent;
# check for a cycle/blossom
base_u = EdmondsBlossomAlgorithm.find_base(base,
parent, current, y)
base_u = EdmondsBlossomAlgorithm.find_base(
base, parent, current, y
)
if base_u != EdmondsBlossomAlgorithm.UNMATCHED:
EdmondsBlossomAlgorithm.contract_blossom(BlossomData(
BlossomAuxData(queue,
parent,
base,
in_blossom,
match,
in_queue),
current, y, base_u))
EdmondsBlossomAlgorithm.contract_blossom(
BlossomData(
BlossomAuxData(
queue,
parent,
base,
in_blossom,
match,
in_queue,
),
current,
y,
base_u,
)
)
# Create result list of matched pairs
matching_result = []
@ -138,15 +158,19 @@ class EdmondsBlossomAlgorithm:
@staticmethod
def contract_blossom(blossom_data: BlossomData):
for x in range(blossom_data.u,
blossom_data.aux_data.base[blossom_data.u] != blossom_data.lca):
for x in range(
blossom_data.u,
blossom_data.aux_data.base[blossom_data.u] != blossom_data.lca,
):
base_x = blossom_data.aux_data.base[x]
match_base_x = blossom_data.aux_data.base[blossom_data.aux_data.match[x]]
blossom_data.aux_data.in_blossom[base_x] = True
blossom_data.aux_data.in_blossom[match_base_x] = True
for x in range(blossom_data.v,
blossom_data.aux_data.base[blossom_data.v] != blossom_data.lca):
for x in range(
blossom_data.v,
blossom_data.aux_data.base[blossom_data.v] != blossom_data.lca,
):
base_x = blossom_data.aux_data.base[x]
match_base_x = blossom_data.aux_data.base[blossom_data.aux_data.match[x]]
blossom_data.aux_data.in_blossom[base_x] = True

15
graphs/tests/test_edmonds_blossom_algorithm.py
View File

@ -4,9 +4,8 @@ from graphs.edmonds_blossom_algorithm import EdmondsBlossomAlgorithm
class EdmondsBlossomAlgorithmTest(unittest.TestCase):
def convert_matching_to_array(self, matching):
""" Helper method to convert a
"""Helper method to convert a
list of matching pairs into a sorted 2D array.
"""
# Convert the list of pairs into a list of lists
@ -21,7 +20,7 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
return result
def test_case_1(self):
""" Test Case 1: A triangle graph where vertices 0, 1, and 2 form a cycle. """
"""Test Case 1: A triangle graph where vertices 0, 1, and 2 form a cycle."""
edges = [[0, 1], [1, 2], [2, 0]]
matching = EdmondsBlossomAlgorithm.maximum_matching(edges, 3)
@ -29,7 +28,7 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
assert expected == self.convert_matching_to_array(matching)
def test_case_2(self):
""" Test Case 2: A disconnected graph with two components. """
"""Test Case 2: A disconnected graph with two components."""
edges = [[0, 1], [1, 2], [3, 4]]
matching = EdmondsBlossomAlgorithm.maximum_matching(edges, 5)
@ -37,7 +36,7 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
assert expected == self.convert_matching_to_array(matching)
def test_case_3(self):
""" Test Case 3: A cycle graph with an additional edge outside the cycle. """
"""Test Case 3: A cycle graph with an additional edge outside the cycle."""
edges = [[0, 1], [1, 2], [2, 3], [3, 0], [4, 5]]
matching = EdmondsBlossomAlgorithm.maximum_matching(edges, 6)
@ -45,7 +44,7 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
assert expected == self.convert_matching_to_array(matching)
def test_case_no_matching(self):
""" Test Case 4: A graph with no edges. """
"""Test Case 4: A graph with no edges."""
edges = [] # No edges
matching = EdmondsBlossomAlgorithm.maximum_matching(edges, 3)
@ -53,7 +52,7 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
assert expected == self.convert_matching_to_array(matching)
def test_case_large_graph(self):
""" Test Case 5: A complex graph with multiple cycles and extra edges. """
"""Test Case 5: A complex graph with multiple cycles and extra edges."""
edges = [[0, 1], [1, 2], [2, 3], [3, 4], [4, 5], [5, 0], [1, 4], [2, 5]]
matching = EdmondsBlossomAlgorithm.maximum_matching(edges, 6)
@ -69,5 +68,5 @@ class EdmondsBlossomAlgorithmTest(unittest.TestCase):
assert result in (possible_matching_1, possible_matching_2)
if __name__ == '__main__':
if __name__ == "__main__":
unittest.main()