gistfile1.rb

def graph_search(graph, initial, queue)
  queue.enqueue(initial)
  seen = {}
  while not queue.empty?
    node = queue.dequeue
    puts node
    seen[node] = true
    if graph[node]
      graph[node].each {|child| queue.enqueue child unless seen[child] }
    end
  end
end

def dfs_search(graph, initial)
  stack = Array.new 
  def stack.enqueue(el); push(el); end
  def stack.dequeue; pop; end
  graph_search(graph, initial, stack)
end

def bfs_search(graph, initial)
  queue = Array.new
  def queue.enqueue(el); push(el); end
  def queue.dequeue; shift; end
  graph_search(graph, initial, queue)
end

graph = {a: [:b, :c], b: [:d, :e], c: [:f, :g]}
dfs_search(graph, :a)
bfs_search(graph, :a)