Python/graphs/kahns_algorithm_long.py
Maxim Smolskiy e3fa014a5a
Fix ruff ()
* updating DIRECTORY.md

* Fix ruff

* Fix

* Fix

* Fix

* Revert "Fix"

This reverts commit 5bc3bf3422.

* find_max.py: noqa: PLR1730

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Co-authored-by: MaximSmolskiy <MaximSmolskiy@users.noreply.github.com>
Co-authored-by: Christian Clauss <cclauss@me.com>
2024-08-25 17:33:11 +02:00

31 lines
772 B
Python

# Finding longest distance in Directed Acyclic Graph using KahnsAlgorithm
def longest_distance(graph):
indegree = [0] * len(graph)
queue = []
long_dist = [1] * len(graph)
for values in graph.values():
for i in values:
indegree[i] += 1
for i in range(len(indegree)):
if indegree[i] == 0:
queue.append(i)
while queue:
vertex = queue.pop(0)
for x in graph[vertex]:
indegree[x] -= 1
long_dist[x] = max(long_dist[x], long_dist[vertex] + 1)
if indegree[x] == 0:
queue.append(x)
print(max(long_dist))
# Adjacency list of Graph
graph = {0: [2, 3, 4], 1: [2, 7], 2: [5], 3: [5, 7], 4: [7], 5: [6], 6: [7], 7: []}
longest_distance(graph)