Class: Algorithmable::Graphs::Traversals::BreadthFirst

Inherits:
Object
  • Object
show all
Includes:
Errors
Defined in:
lib/algorithmable/graphs/traversals/breadth_first.rb

Constant Summary

Constants included from Errors

Errors::TraversalError, Errors::UnvisitedVertexError

Instance Method Summary collapse

Constructor Details

#initialize(graph, source) ⇒ BreadthFirst

Returns a new instance of BreadthFirst.



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# File 'lib/algorithmable/graphs/traversals/breadth_first.rb', line 8

def initialize(graph, source)
  vertices_size = graph.vertices.size
  @visited = Array.new(vertices_size - 1)
  @edge_to = Array.new(vertices_size - 1)
  @source = source
  traverse graph, source
end

Instance Method Details

#path_to(vertex) ⇒ Object 



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# File 'lib/algorithmable/graphs/traversals/breadth_first.rb', line 20

def path_to(vertex)
  fail UnvisitedVertexError, vertex unless visited?(vertex)
  path = []
  finish = vertex
  while finish != @source
    path.push finish
    finish = @edge_to[finish]
  end
  path.push @source
  path
end

#visited?(vertex) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/algorithmable/graphs/traversals/breadth_first.rb', line 16

def visited?(vertex)
  @visited[vertex]
end