procedure inputNumber(op : integer);
var number : string;
    i, chDig : integer;
    isValid : Boolean;
begin
//Input your code here for the inputNumber procedure
if op = 1 then
repeat
writeln('Enter The 12 Digit Number You Want A Check Digit Created For:');
readln(number);
if length(number) = 12 then
getCheckDigit(number,chDig)
else
writeln('Invalid Entry');
until length(number) = 12;
end;

procedure getOption;
var optionStr : string;
    option : integer;
begin
  //Input your code here for the getOption procedure
  repeat
  writeln('(1) Create A Check Digit For A 12 Digit Number');
  writeln('(2) Have A 13 Digit Number Checked To See If The Check Digit Is Valid');
  writeln('Enter A Number For Either Of The Options Above:');
  readln(option);
  if (option < 1) OR (option > 2) then
     writeln('Invald Option')
  until (option = 1) OR (option = 2);
  if option = 1 then
  inputNumber(option)
  else if option = 2 then
  inputNumber(option);

end;