2. Consider the following recursive definition: ifm 0 If n = 0 Otherwise 1, Acker(m,n)-Acker(m- 1,1), Acker(m-1, Acker(m,n -1) This function, called Ackermann's function, is of interest because it grows rapidly with respect to the sizes of m and n. What is Acker (1, 2)? Implement the function in C++ and do a box trace of Acker (1, 2)