var x;

fun printString (s) {
  var i;
  for i := 0, i < s.length, i := i + 1 do
    write (s[i])
  od
}

x := read ();
printString (1.string);
printString ("abc".string);
printString ([].string);
printString ([1, 2, 3].string);
printString (Cons (1, Cons (2, Nil)).string)