Instructions

As a chess enthusiast, you would like to write your own version of the game. Yes, there may be plenty of implementations of chess available online already, but yours will be unique!

Each square of the chessboard is identified by a letter-number pair:

• The horizontal rows of squares, called ranks, are numbered 1 through 8.
• The vertical columns of squares, called files, are labeled A through H.

   A B C D E F G H
 8 # _ _ _ # _ _ # 8
 7 _ _ _ _ _ _ _ _ 7
 6 _ _ _ _ # _ _ # 6
 5 _ # _ _ _ _ _ # 5
 4 _ _ _ _ _ _ # # 4
 3 # _ # _ _ _ _ # 3
 2 _ _ _ _ _ _ _ # 2
 1 # _ _ _ _ _ _ # 1
   A B C D E F G H

1. Given a Chessboard and a File, count how many squares are occupied

Implement the CountInFile(board Chessboard, file string) int function. It should count the total number of occupied squares by ranging over a map. Return an integer. Return a count of zero (0) if the given file cannot be found in the map.

2. Given a Chessboard and a Rank, count how many squares are occupied

Implement the CountInRank(board Chessboard, rank int) int function. It should count the total number of occupied squares by ranging over the given rank. Return an integer. Return a count of zero (0) if the given rank is not a valid one (not between 1 and 8, inclusive).

3. Count how many squares are present in the given chessboard

Implement the CountAll(board Chessboard) int function. It should count how many squares are present in the chessboard and returns an integer. Since you don't need to check the content of the squares, consider using range omitting both index and value.

4. Count how many squares are occupied in the given chessboard

Implement the CountOccupied(board Chessboard) int function. It should count how many squares are occupied in the chessboard. Return an integer.