program case_of_statement;
var
  n : integer;
begin
  repeat
    write('Enter number smaller than 5 (n <= 4) : ');
    readln(n);
    if n > 4 then
    begin
      writeln(n, '>', 4);
      writeln('Retry !');
    end;
  until n <= 4;
  case n of
    0 : writeln('zero');
    1 : writeln('one');
    2 : writeln('two');
    3 : writeln('three');
    4 : writeln('four');
  end;
  readln;
end.
{if you want to improve this code, please send code to me
tranleduy1233@gmail.com}