{
This program illustrates the use of the predeclared procedure
exit:
}


program three6;

  var
    i: integer;

  procedure alpha;
    forward;
  procedure beta;
    forward;
  procedure gamma;
    forward;

  procedure alpha;
    begin
      beta;
      writeln('Exit alpha');
    end;  { alpha }

  procedure beta;
    begin
      gamma;
      writeln('Exit beta');
    end;  { beta }

  procedure gamma;
    begin
      write('Please enter a digit: ');
      readln(i);
      writeln;
      writeln('Thank you');
      case i of
        1: exit(three6);
        2: exit(alpha);
        3: exit(beta);
        4: exit(gamma);
      end;  { case }
      writeln('Exit gamma');
    end;  { gamma }

  begin
    alpha;
    writeln('Exit program');
  end.  { 3-6 }


{ Executing this program will result in the following output
  sequences, depending upon the value of <n>:


Please enter a digit: <n>     { <n> is entered by the user }

Thank you     Thank you     Thank you     Thank you     Thank you
              Exit program  Exit alpha    Exit beta     Exit gamma
                            Exit program  Exit alpha    Exit beta
                                          Exit program  Exit alpha
                                                        Exit program

 {<n> = 1}     {<n> = 2}     {<n> = 3}     {<n> = 4}     {<n> >= 5 or
                                                          <n> <= 0}
}