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1f8a21d727
* Tighten up psf/black and flake8
* Fix some tests
* Fix some E741
* Fix some E741
* updating DIRECTORY.md
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
43 lines
976 B
Python
43 lines
976 B
Python
# Finding Bridges in Undirected Graph
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def computeBridges(graph):
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id = 0
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n = len(graph) # 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 graph[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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graph = {
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0: [1, 2],
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1: [0, 2],
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2: [0, 1, 3, 5],
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3: [2, 4],
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4: [3],
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5: [2, 6, 8],
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6: [5, 7],
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7: [6, 8],
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8: [5, 7],
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}
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computeBridges(graph)
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