arraylist

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

namespace activity1
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] letter = new string[9];
            letter[0] = "";
            letter[1] = "B";
            letter[2] = "A";
            letter[3] = "D";
            letter[4] = "C";
            letter[5] = "F";
            letter[6] = "E";
            letter[7] = "H";
            letter[8] = "G";

            /*
             * 1.0=2
             * 2.1=1
             * 3.2=4
             * 4.3=3
             * 5.4=6
             * 6.5=5
             * 7.6=8
             * 8.7=7
             * */

            letter[0] = letter[2];
            letter[1] = letter[1];
            letter[2] = letter[4];
            letter[3] = letter[3];
            letter[4] = letter[6];
            letter[5] = letter[5];
            letter[6] = letter[8];
            letter[7] = letter[7];

            Console.WriteLine(letter[0]+"\t"+letter[1]+"\t"+letter[2]
                +"\t"+letter[3]+"\t"+letter[4]+"\t"+letter[5]+"\t"+letter[6]
                +"\t"+letter[7]);
            Console.ReadLine();
        }
    }
}