class Main inherits IO {
    pal(s : String) : Bool {
	if s.length() = 0
	then true
	else if s.length() = 1
	then true
	else if s.substr(0, 1) = s.substr(s.length() - 1, 1)
	then pal(s.substr(1, s.length() -2))
	else false
	fi fi fi
    };

    s : String;
    
    print_pal(s : String) : IO {
      if pal(s)
      then out_string(s.concat(" is a palindrome\n"))
      else out_string(s.concat(" is not a palindrome\n"))
      fi
    };

    main() : Object {
	{
            s <- "amanaplanacanalpanama";
            print_pal(s);
            s <- "hello";
            print_pal(s);   
	}
    };
};