WITH useful;
WITH addQueen;
WITH ada.text_io;
PROCEDURE Queen IS

        -- records blocked positions     
   FreeColumn       : useful.ColumnFree;
   UpDiagonalFree   : useful.UpFree ;
   DownDiagonalFree : useful.DownFree;

        -- controls search
   Row              : Useful.ZeroToEight;

        -- records placement of queens
   ColumnArray      : Useful.Columns;

        -- counters
   Tried            : integer := 0;          -- counts queens placed
   Tested           : integer := 0;          -- counts positions tested   

        -- output file
   Board            : ada.text_io.file_type;  -- keeps success record & text

BEGIN
          -- prepare file for use
   ada.text_io.create (file => board,
                     mode => ada.text_io.out_file,
                 name => "a:\writeboard.out");

           -- initializations
   Row := 0;
   FreeColumn  := (OTHERS => true);
   UpDiagonalFree:= (OTHERS => true);
   DownDiagonalFree := (OTHERS => true);
   
           -- do work
   AddQueen (R     => Row,
             UpF   => UpDiagonalFree,
             DownF => DownDiagonalFree,     
             FreeC => FreeColumn,
             Col   => ColumnArray, 
             Tried => Tried,
             Tested => Tested,
             Solutions =>Board);

   --   when arrive here, work done so close output files
   ada.text_io.close (file => Board);

END Queen;