CONTROL X'10000000' ;  ! Decode
BEGIN
  INTEGERFN ACKERMANN(INTEGER M, N)

   RESULT = N+1 IF M = 0

   RESULT = ACKERMANN(M-1, 1) IF N = 0

   RESULT = ACKERMANN(M-1, ACKERMANN(M, N-1))

  END

  INTEGER I

  I = ACKERMANN(3,4)

  PRINT STRING("Ackermann(3,4) = "); WRITE(I, 0); NEWLINE
  
ENDOFPROGRAM