FilesExpand file tree

 master

/

ackermann_memo.py

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

35 lines (25 loc) · 702 Bytes

 master

/

ackermann_memo.py

Copy path

Top

File metadata and controls

• Code
• Blame

35 lines (25 loc) · 702 Bytes

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

"""This module contains a code example related to

Think Python, 2nd Edition

by Allen Downey

http://thinkpython2.com

Copyright 2015 Allen Downey

License: http://creativecommons.org/licenses/by/4.0/

"""

from __future__ import print_function, division

cache = {}

def ackermann(m, n):

"""Computes the Ackermann function A(m, n)

See http://en.wikipedia.org/wiki/Ackermann_function

n, m: non-negative integers

"""

if m == 0:

return n+1

if n == 0:

return ackermann(m-1, 1)

try:

return cache[m, n]

except KeyError:

cache[m, n] = ackermann(m-1, ackermann(m, n-1))

return cache[m, n]

print(ackermann(3, 4))

print(ackermann(3, 6))