string[] letters = new string[8];
for (int i = 0; i < letters.Length; i++)
letters[i] = ((char)(65 + i)).ToString();
for (int i = 8; i > 0; i--)
{
for (int j = 0; j < letters.Length; j++)
{
Console.Write(letters[j] + (i) + " ");
}
Console.WriteLine();
}