-- $Id: ackermann.lua,v 1.5 2000/12/09 20:07:43 doug Exp $ -- http://www.bagley.org/~doug/shootout/ -- contributed by Roberto Ierusalimschy function Ack(M, N) if M == 0 then return N + 1 elseif N == 0 then return Ack(M - 1, 1) else return Ack(M - 1, Ack(M, (N - 1))) end end NUM = tonumber((arg and arg[1])) or 1 io.write("Ack(3,", NUM ,"): ", Ack(3,NUM), "\n")