namespace 
{
    using System;
    using System.Collections;

    internal sealed class 
    {
        private  
;
        private  ;
        private Ÿ  = new Ÿ();
        private Ÿ  = new Ÿ();
        private ArrayList  = new ArrayList();
        private ArrayList  = new ArrayList();

        private void ‰(object ANodeList)
        {
            Console.WriteLine("Node list:");
            foreach (  in ANodeList as IEnumerable)
            {
                .‡();
            }
            Console.WriteLine("=====");
        }

        public void Š( AStartNode,  AGoalNode)
        {
            this.
 = AStartNode;
            this. = AGoalNode;
            this..Add(this.
);
            while (this..Count > 0)
            {
                  = () this..‰();
                if (.†())
                {
                    while ( != null)
                    {
                        this..Insert(0, );
                         = .();
                    }
                    break;
                }
                .(this.);
                foreach ( 2 in this.)
                {
                     3 = null;
                    if (this..Contains(2))
                    {
                        3 = () this.[this..IndexOf(2)];
                    }
                    if ((3 == null) || (2.() <= 3.()))
                    {
                         4 = null;
                        if (this..Contains(2))
                        {
                            4 = () this.[this..IndexOf(2)];
                        }
                        if ((4 == null) || (2.() <= 4.()))
                        {
                            this..Remove(3);
                            this..Remove(4);
                            this..Š(2);
                        }
                    }
                }
                this..Add();
            }
        }

        public ArrayList Solution
        {
            get
            {
                return this.;
            }
        }
    }
}