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42 lines
654 B
Ruby
42 lines
654 B
Ruby
class BFS
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attr_accessor :graph, :s, :visited, :edge_to
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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 = [@s]
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@edge_to = {}
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bfs
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end
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def bfs
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queue = [@s]
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while queue.length > 0
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node = queue.shift
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@graph[node].each do |child_node|
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next if @visited.include?(child_node)
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queue.push(child_node)
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@visited << child_node
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@edge_to[child_node] = node
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end
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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 shortest_path(v)
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stack = [v]
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while v != @s
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v = @edge_to[v]
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stack.push(v)
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end
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stack.push(@s)
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end
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end
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