39 lines
560 B
Ruby
39 lines
560 B
Ruby
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class DFS
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attr_reader :graph
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def initialize(graph, s)
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@graph = graph
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@s = s
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@visited = []
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@edge_to = {}
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dfs(@graph, @s)
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end
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def dfs(graph, s)
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@visited << s
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@graph[s].each do |node|
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next if @visited.include? node
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dfs(graph, node)
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@edge_to[node] = s
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end
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end
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def path_to?(v)
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@visited.include?(v)
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end
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def trace_path(v)
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return false unless path_to?(v)
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path = []
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until v == @s
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v = @edge_to[v]
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path.unshift(v)
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end
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path.unshift(@s)
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path
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end
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end
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