Pascal Cli calculator.

program calcattempt;

{$mode objfpc}{$H+}

uses
  {$IFDEF UNIX}{$IFDEF UseCThreads}
  cthreads,
  {$ENDIF}{$ENDIF}
  Classes
  { you can add units after this };
  var
  num1:integer;
  num2:integer;
  P1:char;
  Sel:string;


{$IFDEF WINDOWS}{$R calcattempt.rc}{$ENDIF}

begin
repeat
 writeln('---------Mcalc-------------');
 writeln('  Press <ENTER> To Continue');
 writeln('---------------------------');
 readln;

repeat
 write('Please Select Your Operation, A = +, B = - , C = /, or D = *: ');
 readln(P1);
 writeln;
 writeln('incorrect format');
until (P1 = 'A') or (P1 = 'a') or (P1 = 'B') or (P1 = 'b') or (P1 = 'C') or (P1 = 'c') or (P1 = 'D') or (P1 = 'd');
 writeln('So you have picked ', P1);
 writeln;
 write('Please Enter your First Number: ');
 readln(num1);
 write('Now Your Second Number: ');
 readln(num2);
 writeln;
  case P1 of
    'D','d':begin
     writeln('Your Calculation is: ', num1*num2);
            end;
  end;
  case P1 of
   'A','a':begin
    writeln('Your Calculation is: ', num1+num2);
           end;
 end;
 case P1 of
  'B','b':begin
   writeln('Your Calculation is: ', num1-num2);
         end;
 end;
 case P1 of
  'C','c':begin
   writeln('Your Calculation is: ', num1/num2:0:2);
          end;
 end;
 writeln;
 write('Press "A" To Exit Or "B" To Continue: ');
 readln(sel);
 writeln;
 writeln;
 until (sel = 'A') or (sel = 'a');



end.