35 lines
660 B
Ruby
35 lines
660 B
Ruby
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# needs refactoring
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class BFS
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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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end
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def bfs(target)
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return true if target == @s
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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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return true if child_node == target
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next if @visited.include? child_node
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queue.push(child_node)
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@visited.push(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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false
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end
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def path_to?(node)
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path = []
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until node == @s
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path.unshift(node)
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node = @edge_to[node]
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end
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path
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end
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end
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