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Fixed

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This commit is contained in:
VarshiniShreeV 2024-10-27 00:21:12 +05:30
parent 03a42510b0
commit 3ceccfb59c
1 changed files with 4 additions and 23 deletions
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27
sorts/topological_sort.py
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@ -1,10 +1,3 @@
"""Topological Sort."""
# a
# / \
# b c
# / \
# d e
edges: dict[str, list[str]] = { edges: dict[str, list[str]] = {
"a": ["c", "b"], "a": ["c", "b"],
"b": ["d", "e"], "b": ["d", "e"],
@ -14,28 +7,16 @@ edges: dict[str, list[str]] = {
} }
vertices: list[str] = ["a", "b", "c", "d", "e"] vertices: list[str] = ["a", "b", "c", "d", "e"]
def topological_sort(start: str, visited: list[str], sort: list[str]) -> list[str]: def topological_sort(start: str, visited: list[str], sort: list[str]) -> list[str]:
"""Perform topological sort on a directed acyclic graph.""" visited.append(start)
current = start current = start
# add current to visited for neighbor in edges[start]:
visited.append(current)
neighbors = edges[current]
for neighbor in neighbors:
# if neighbor not in visited, visit
if neighbor not in visited: if neighbor not in visited:
sort = topological_sort(neighbor, visited, sort) topological_sort(neighbor, visited, sort)
# if all neighbors visited add current to sort
sort.append(current) sort.append(current)
# if all vertices haven't been visited select a new one to visit
if len(visited) != len(vertices):
for vertice in vertices:
if vertice not in visited:
sort = topological_sort(vertice, visited, sort)
# return sort
return sort return sort
if __name__ == "__main__": if __name__ == "__main__":
sort = topological_sort("a", [], []) sort = topological_sort("a", [], [])
sort.reverse() #Top down approach
print(sort) print(sort)