def ackermann(m,n):
     if   m == 0:
            return (n + 1)
     elif n == 0:
            return ackermann(m - 1, 1)
     else:
            return ackermann(m - 1, ackermann(m, n - 1)) 
          
x=int(input("m =  "))

y=int(input("n =  "))

print ("Ackermann(",x,",",y,") = ",ackermann(x, y))