F#

Exercise 2.8 The Ackermann function is a recursive function where both value and number of mutually recursive calls grow rapidly.

Write the function ack: int * int -> int that implements the Ackermann function using pattern matching on the cases of (m,n) as given below. A(m, n) = n + 1 if m = 0 A(m 1, 1) if m > 0 and n = 0 A(m 1, A(m, n 1)) if m > 0 and n > 0 What is the result of ack(3,11). Notice: The Ackermann function is defined for non negative numbers only.