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32 lines
909 B
Python
32 lines
909 B
Python
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# Finding Bridges in Undirected Graph
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def computeBridges(l):
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id = 0
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n = len(l) # No of vertices in graph
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low = [0] * n
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visited = [False] * n
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def dfs(at, parent, bridges, id):
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visited[at] = True
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low[at] = id
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id += 1
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for to in l[at]:
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if to == parent:
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pass
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elif not visited[to]:
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dfs(to, at, bridges, id)
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low[at] = min(low[at], low[to])
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if at < low[to]:
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bridges.append([at, to])
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else:
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# This edge is a back edge and cannot be a bridge
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low[at] = min(low[at], to)
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bridges = []
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for i in range(n):
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if (not visited[i]):
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dfs(i, -1, bridges, id)
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print(bridges)
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l = {0:[1,2], 1:[0,2], 2:[0,1,3,5], 3:[2,4], 4:[3], 5:[2,6,8], 6:[5,7], 7:[6,8], 8:[5,7]}
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computeBridges(l)
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