layout.cs

最大宽度搜索法来解决华容道问题

using System;
using System.Collections;

namespace HRD.Core
{
	public class Layout
	{
		private Mediator _mediator;
		private Chessman[] _chessmen = new Chessman[10];

		private bool _gotTheAnswer = false;
		private int _current = 0;

		private BlankPosition _blankPosition;

		#region 搜索可行布局并封装

		//===========================================================
		// 根据当前棋盘布局获取下一步可走的方案
		//===========================================================
		public void CheckAvailableSteps()
		{
			CallBackDelegate _callback = new CallBackDelegate(EncapsulateChessStep);

			for(_current = 0; _current<10; _current++)
				_chessmen[_current].CheckAvailableSteps(_blankPosition, _callback);

		}

		//===========================================================
		// 获取移动棋子后，棋盘的布局
		//===========================================================
		private void EncapsulateChessStep(int newPosition, BlankPosition newBlankPosition, MoveMethod mm)
		{
			if( _gotTheAnswer )
				return;

			Layout l = _mediator.AllocateLayout();
			
			// 生成新布局
			for(int i = 0; i<10; i++)
			{
				if(i == _current)
					l.chessmen[i].position = newPosition;
				else
					l.chessmen[i].position = this.chessmen[i].position;
			}

			l.blankPosition = newBlankPosition;

			ChessStep cs = new ChessStep();
			cs.layout = l.ToInt64();
			cs.chessmanPosition = this.chessmen[_current].position;
			cs.moveMethod = mm;

			// 将封装好的ChessStep发送给mediator作进一步处理
			if(l.IsFinished)
			{
				_gotTheAnswer = true;
				_mediator.Finished(cs);
			}
			else
				_mediator.CheckStep(cs);
		}

		#endregion
		
		#region 将棋局转换整数

		//===========================================================
		// 将当前棋局转换为一整数
		//===========================================================
		public Int64 ToInt64()
		{

			Int64 result = 0;
			Int64 typeCode, positionCode;
			
			for(int i=0; i<10; i++)
			{
				typeCode = (int)_chessmen[i].chessmanType;
				positionCode = _chessmen[i].position - (_chessmen[i].position/8) * 4;

				result += typeCode << ((int)(3 * positionCode));
			}

			return result;
		}

		#endregion

		#region Property Method

		public bool IsFinished
		{
			get
			{
				for(int i=0; i<10; i++)
					if(_chessmen[i].chessmanType == ChessmanType.General && 
						_chessmen[i].position == 25)
						return true;

				return false;
			}
		}

		public Chessman[] chessmen 
		{
			get 
			{
				return _chessmen;
			}
			set 
			{
				_chessmen = value;
			}
		}

		public BlankPosition blankPosition 
		{
			get 
			{
				return _blankPosition;
			}
			set 
			{
				_blankPosition = value;
			}
		}

		public Mediator mediator 
		{
			set 
			{
				_mediator = value;
			}
		}

		#endregion
	}
}