treearithmetic.cs

这是有一个解决八数码问题的程序！ 主要应用了宽度优先搜索法！ 是用C#开发的

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;

using DS.Tree;
namespace JiuGong
{
    public class TreeArithmetic
    {
        public BinaryTree Tree = new BinaryTree();
        public string Init = "";
        public string Aim = "";
        public ArrayList m_pScanbuf = new ArrayList();
        public ArrayList BestPath = new ArrayList();
        private int row = -1;
        private int col = -1;
        #region 声明属性
        public int Row
        {
            get
            {
                return this.row;
            }
            set
            {
                this.row = value;
            }
        }
        public int Col
        {
            get
            {
                return this.col;
            }
            set
            {
                this.col = value;
            }
        }
        #endregion
        public struct Scanbuf
        {
            public string Place;
            public int ScanID;
        }
        public TreeArithmetic(string Init, string Aim, int Row, int Col)
        {
            this.Init = Init;
            this.Aim = Aim;
            this.Row = Row;
            this.Col = Col;
        }
        //添加树中节点
        //public bool AddTree(string place,TreeNode Node )
        //{
        //    if (Node == null)
        //    {
        //        Node=new TreeNode(place);
        //        //刚开始没有加此，发生一直都返回false的情况
        //        return true;
        //    }
        //    if (Node.Item.ToString() == place)
        //    {
        //        return false;
        //    }
        //    if (Int32.Parse(Node.Item.ToString())> Int32.Parse(place))
        //    {
        //       return AddTree(place, Node.RightChild);
        //    }
        //    return AddTree(place, Node.LeftChild);
        //}
        public bool AddTree(string place, TreeNode node, TreeNode root)
        {
            if (root == null)
            {
                root = new TreeNode(place);
                return true;
            }
            if (node.Item.ToString() == place)
            {
                return false;
            }
            if (Int32.Parse(node.Item.ToString()) > Int32.Parse(place))
            {
                if (node.LeftChild == null)
                {
                    node.LeftChild = new TreeNode(place);
                    return true;
                }
                else
                {
                    return AddTree(place, node.LeftChild, root);
                }
            }
            else
            {
                if (node.RightChild == null)
                {
                    node.RightChild = new TreeNode(place);
                    return true;
                }
                else
                {
                    return AddTree(place, node.RightChild, root);

                }
            }
        }
        public void FreeTree(TreeNode root)
        {
            if (root.LeftChild != null)
            {
                FreeTree(root.LeftChild);
            }
            else if (root.RightChild != null)
            {
                FreeTree(root.RightChild);
            }
            else
            {
                root = null;
            }
        }
        public bool ComputeFeel()
        {
            const int MAXSIZE = 362880;
            string target = this.Aim, fountain = this.Init, parent = "";
            int parentID = 0, child = 1;
            string[] NextStates;
            Scanbuf temp;

            if (fountain == target)
            {
                return false;
            }
            if (m_pScanbuf.Count > 0)
            {
                m_pScanbuf.Clear();
            }

            this.Tree.Root = new TreeNode(fountain);
            AddTree(fountain, Tree.Root, Tree.Root);

            Scanbuf buf = new Scanbuf();
            buf.Place = fountain;
            buf.ScanID = -1;
            m_pScanbuf.Add(buf);


            while (parentID < MAXSIZE && child < MAXSIZE)
            {
                if (parentID < child)
                {
                    temp = (Scanbuf)m_pScanbuf[parentID];
                    parent = temp.Place;
                    NextStates = GetNextStates(parent.ToString());
                    for (int i = 0; i < 4; i++)
                    {
                        if (NextStates[i] != "")
                        {
                            fountain = NextStates[i];
                            if (AddTree(fountain, Tree.Root, Tree.Root))
                            {
                                buf.Place = fountain;
                                buf.ScanID = parentID;
                                m_pScanbuf.Add(buf);
                                if (fountain == target)
                                {
                                    GetPath(child);
                                    m_pScanbuf.Clear();
                                    FreeTree(this.Tree.Root);
                                    return true;
                                }
                                child++;
                            }
                        }
                    }               
                }
                parentID++;
            }
            m_pScanbuf.Clear();
            FreeTree(this.Tree.Root);
            this.BestPath.Clear();
            return false;
        }
        #region 获取下一个可能状态
        public string[] GetNextStates(string sInitState)
        {
            string[] NextStates ={ "", "", "", "" };
            int i = 0;
            //数字0在sInitState中的下标
            int indexZero = sInitState.IndexOf('0');
            char[] Array = sInitState.ToCharArray();
            //此下标对应与假想的二维数组中的行、列坐标
            int X = -1, Y = -1;
            X = (int)indexZero / 3;
            Y = indexZero % 3;
            //将要移动的一个数字在sInitState中的下标
            int indexMove = -1;
            char c;

            if (X != -1 && Y != -1)
            {
                //是否可以向左移动
                if (Y < col - 1)
                {
                    indexMove = X * 3 + (Y + 1);
                    c = Array[indexMove];
                    Array[indexMove] = '0';
                    Array[indexZero] = c;
                    NextStates[i] = new string(Array);
                    i++;
                    Array = sInitState.ToCharArray();

                }
                //是否可以向右移动
                if (Y >= 1)
                {
                    indexMove = X * 3 + (Y - 1);
                    c = Array[indexMove];
                    Array[indexMove] = '0';
                    Array[indexZero] = c;
                    NextStates[i] = new string(Array);
                    i++;
                    Array = sInitState.ToCharArray();
                }
                //是否可以向上移动
                if (X < Row - 1)
                {
                    indexMove = (X + 1) * 3 + Y;
                    c = Array[indexMove];
                    Array[indexMove] = '0';
                    Array[indexZero] = c;
                    NextStates[i] = new string(Array);
                    i++;
                    Array = sInitState.ToCharArray();
                }
                //是否可以向下移动
                if (X > 0)
                {
                    indexMove = (X - 1) * 3 + Y;
                    c = Array[indexMove];
                    Array[indexMove] = '0';
                    Array[indexZero] = c;
                    NextStates[i] = new string(Array);
                    i++;
                    Array = sInitState.ToCharArray();
                }
            }
            return NextStates;
        }
        #endregion
        public void GetPath(int child)
        {
            ArrayList Path = new ArrayList();
            int ParentID = child;
            Scanbuf temp;
            while (ParentID != -1)
            {
                temp = (Scanbuf)m_pScanbuf[ParentID];
                Path.Add(temp.Place.ToString());
                ParentID = temp.ScanID;
            }
            Path.Reverse();
            this.BestPath.Clear();
            this.BestPath.AddRange(Path);
        }


    }
    //
}