Ackermann Function

ackermanns

#!/usr/bin/python
# pylint: disable=C0103
"""
A function which outputs the Ackermann values for M and N

Citation: Weisstein, Eric W. "Ackermann Function." From MathWorld--A Wolfram Web Resource.
http://mathworld.wolfram.com/AckermannFunction.html
"""

M = 3
N = 3
I = [0]

def ack(m, n):
    """Ackermann's Function"""
    I[0] += 1
    if m == 0:
        return n + 1
    elif n == 0:
        return ack(m - 1, 1)
    else:
        return ack(m - 1, ack(m, n - 1))

print "Ackermann Value for {} and {}: {}".format(M, N, ack(3, 3))
print "Iterations: {}".format(I)