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