(* ==============================================================================
 *    File: GradeCalculator.p
 *  Purpose: Simple program to calculate the percentage and letter grade
 *  Author: Jordan Kidney ( kidney@cpsc.ucalgary.ca )
 * Created on: Feb 14, 2006
  ============================================================================== *)
program GradeCalculator (input,output);

(* ========================== MAIN ============================================== *)
begin
      var Mark        : real; (* The mark the user got *) 
      var TotalMarks  : real; (* Total number of possible marks *)
      var Percentage  : real; (* Used to store the calculated percentage value *)	
      var LetterGrade : char; (* Used to store the letter cade for the mark *)
      var LetterSign  : char; (* Used to store the sign for the letter grade *)
      var EndLoop     : boolean; (* Used as a flag to end loops for error checking *)	

      (* Read in the total marks for the test and make sure
       * it is greaterr then zero                                 *)
	 
      EndLoop := false;
      repeat
          write('Enter the total number of marks : ');
          readln(TotalMarks);
	  if (TotalMarks <= 0) then 
               writeln('Error: The number must be greater then zero.')
	  else
	     EndLoop := true

      until EndLoop = true;

      (* Read in the mark the user got and make sure
       * that it is grwater ten or equal to zero and les then the
       *  total number of marks for the test                      *)

       EndLoop := false;
       repeat
          write('Enter your mark : ');
          readln(Mark);
          if ((Mark < 0) or (Mark > TotalMarks))  then
	     writeln('Error: inncorect input')
	  else
	     EndLoop := true

       until EndLoop = true;

      (* Calculate the percentage value for the user *)
      Percentage := (Mark * 100.0)/TotalMarks;		

      (* Find the letter grade based upon the percentage value found *)
      if (Percentage < 39.0) then
	 begin
	    LetterGrade := 'F'; LetterSign  := ' ';
	 end
      else if (Percentage < 44.0) then
         begin
           LetterGrade := 'D'; LetterSign  := '-';
	 end
      else if (Percentage < 49.0) then
	 begin
	    LetterGrade := 'D'; LetterSign  := ' ';
	 end
      else if (Percentage < 54.0) then
	 begin
	    LetterGrade := 'D'; LetterSign  := '+';
	 end
      else if (Percentage < 59.0) then
	 begin
	    LetterGrade := 'C'; LetterSign  := '-';
	 end
      else if (Percentage < 64.0) then
	 begin
	    LetterGrade := 'C'; LetterSign  := ' ';
	 end
      else if (Percentage < 69.0) then
	 begin
	    LetterGrade := 'C'; LetterSign  := '+';
	 end
      else if (Percentage < 74.0) then
	 begin
	    LetterGrade := 'B'; LetterSign  := '-';
	 end
      else if (Percentage < 79.0) then
	 begin
	    LetterGrade := 'B'; LetterSign  := ' ';
	 end
      else if (Percentage < 84.0) then
	 begin
	    LetterGrade := 'B'; LetterSign  := '+';
	 end
      else if (Percentage < 89.0) then
	 begin
	    LetterGrade := 'A'; LetterSign  := '-';
	 end
      else 
	 begin
	    LetterGrade := 'A'; LetterSign  := ' ';
	 end;
         
      (* Write information to the console *)
      writeln('You got ',
               Percentage:0:2,
	      '% on the test which gives you a letter grade of '
	      ,LetterGrade,LetterSign);
end.
(* ============================================================================== *)