const
   maxbit = 40;
type
   bitnumber = 0..39;
   bitmap = record
      bits:  array[0..4] of byte;       {bits 0..39}
   end;

function getbit(map: bitmap; bitnum: bitnumber): boolean;
   {return true/false for specified bit in a bitmap}
procedure setbit(var map: bitmap; bitnum: bitnumber; value: boolean);
   {set the specified bit in a bitmap}