Part VIII : Bidirectional Search

v      Bidirectional Search

public static void Bidirectional_Search(Node Start,Node Goal)

        {

            GetSucc x = new GetSucc();

            ArrayList Children_1 = new ArrayList();

            ArrayList Children_2 = new ArrayList();

            Queue Fringe_IN = new Queue();

            Queue Fringe_GO = new Queue();

            Fringe_IN.Enqueue(Start);

            Fringe_GO.Enqueue(Goal);

            while((Fringe_IN.Count !=0)&&(Fringe_GO.Count!=0))

            {

                Node Parent1 = (Node)Fringe_IN.Dequeue();

                Console.WriteLine("Node {0} Visited ", Parent1.State);

                //Console.ReadKey();

                if ((Parent1.State == Goal.State)||Contain(Fringe_GO,Parent1))

                {

                    Console.WriteLine();

                    Console.WriteLine("Find Goal   " + Parent1.State);

                    break;

                }//end if

                Children_1 = x.GetSussessor(Parent1.State);

                for (int i = 0; i < Children_1.Count; i++)

                {

                    int State = (int)Children_1[i];

                    Node Tem = new Node(State, Parent1);

                    Fringe_IN.Enqueue(Tem);

                }//end for

                Node Parent2 = (Node)Fringe_GO.Dequeue();

                Console.WriteLine("Node {0} Visited ", Parent2.State);

                //Console.ReadKey();

                if ((Parent2.State == Start.State) || Contain(Fringe_IN,Parent2))

                {

                    Console.WriteLine();

                    Console.WriteLine("Find Goal   " + Parent2.State);

                    break;

                }//end if

                Children_2 = x.GetSussessor_Reverse(Parent2.State);

                for (int i = 0; i < Children_2.Count; i++)

                {

                    int State = (int)Children_2[i];

                    Node Tem = new Node(State, Parent2);

                    Fringe_GO.Enqueue(Tem);

                }//end for

            }//end while

        }//End Method

public static bool Contain(Queue Fringe,Node Parent)

        {

            object[] S = new object[Fringe.Count];

            S = Fringe.ToArray();

            for (int i = 0; i < S.Length; i++)

            {

                Node Target = (Node)S[i];

                if (Target.State == Parent.State)

                {

                    return true;

                }

            }

            return false;

        }