从google doc转移-8皇后

using System.Collections.Generic;

using System.Windows.Forms;

using System.IO;

 

namespace zboDo.ACM

{

    class EightQueen

    {

        private List<GridCell> ArrangedList;

        public void printAllGridCells()

        {

            string s = string.Empty;

            foreach (GridCell c in ArrangedList)

            {

                s += "{" + c.xValue + "," + c.yValue +"}";

            }

            //MessageBox.Show(s);

            FileInfo t = new FileInfo(@"c:/result.txt");

            TextWriter Tex = t.AppendText();

            Tex.WriteLine(s);

            Tex.Close();

        }

        public void Run()

        {

            ClearBeforeResult();

            ArrangedList=new List<GridCell>();

            int row=0;

            int col = 0;

            putCell(row, col);

        }

 

        private void ClearBeforeResult()

        {

            FileInfo t = new FileInfo(@"c:/result.txt");

            if(File.Exists(@"c:/result.txt"))

            {

                t.Delete();

            }

        }

 

        private void putCell(int row, int col)

        {

            while (row < 8)

            {

                GridCell cell = makeGridCell(row, col);

                if (ISLegal(cell))

                {

                    ArrangedList.Add(cell);

                    if (col < 7)

                    {

                        putCell(0, col + 1);

                    }

                    else

                    {

                        printAllGridCells();

                        this.RemovelastNode();

                    }

                }

                row++;

            }

            this.RemovelastNode();

            col--;

        }

        private void RemovelastNode()

        {

            if(ArrangedList.Count>0)

            ArrangedList.RemoveAt(ArrangedList.Count - 1);

        }

 

        private bool ISLegal(GridCell cell)

        {

            bool result=true;

            foreach (GridCell gridCell in ArrangedList)

            {

                if (gridCell.xValue == cell.xValue) result = false;

                else if (gridCell.yValue == cell.yValue) result = false;

                else if (gridCell.yValue+gridCell.xValue == cell.yValue+cell.xValue) result = false;

                else if (gridCell.yValue-gridCell.xValue == cell.yValue-cell.xValue) result = false;

            }

            return result;

        }

 

        private GridCell makeGridCell(int row, int col)

        {

            GridCell cell=new GridCell();

            cell.xValue = row;

            cell.yValue = col;

            return cell;

        }

 

        class GridCell

        {

           public int xValue;

           public int yValue;

        }

    }

}