array suffix = {"th", "st", "nd", "rd"}

text ordinal(int num)
  num mod 100
  if (num > 9) and (num < 20)
    num = 0
  else
    num mod 10
    if num > 3 let num = 0
  /if
return suffix[num].toText()


int main(int argc, array argv)
  for int i in 0 -- 20
     print i, ordinal(i)
  /for
return 0

main($argc, $argv)