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31 lines
767 B
Python
31 lines
767 B
Python
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# Finding longest distance in Directed Acyclic Graph using KahnsAlgorithm
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def longestDistance(l):
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indegree = [0] * len(l)
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queue = []
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longDist = [1] * len(l)
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for key, values in l.items():
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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 l[vertex]:
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indegree[x] -= 1
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if longDist[vertex] + 1 > longDist[x]:
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longDist[x] = longDist[vertex] + 1
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if indegree[x] == 0:
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queue.append(x)
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print(max(longDist))
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# Adjacency list of Graph
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l = {0:[2,3,4], 1:[2,7], 2:[5], 3:[5,7], 4:[7], 5:[6], 6:[7], 7:[]}
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longestDistance(l)
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