Problem:
Score : 300 points

Problem Statement

To make it difficult to withdraw money, a certain bank allows its customers to withdraw only one of the following amounts in one operation:

1 yen (the currency of Japan)

6 yen, 6^2(=36) yen, 6^3(=216) yen, ...

9 yen, 9^2(=81) yen, 9^3(=729) yen, ...

At least how many operations are required to withdraw exactly N yen in total?

It is not allowed to re-deposit the money you withdrew.

Constraints

1 \leq N \leq 100000

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

If at least x operations are required to withdraw exactly N yen in total, print x.

Sample Input 1

127

Sample Output 1

4

By withdrawing 1 yen, 9 yen, 36(=6^2) yen and 81(=9^2) yen, we can withdraw 127 yen in four operations.

Sample Input 2

3

Sample Output 2

3

By withdrawing 1 yen three times, we can withdraw 3 yen in three operations.

Sample Input 3

44852

Sample Output 3

16

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

import itertools as i
n=int(input())
ans=0
while 1:
    a=list(i.takewhile(lambda i:9**i<=n,(i for i in range(100))))[-1]
    n-=9**a
    ans+=1
    if n==0:
        break
    b=list(i.takewhile(lambda i:9**i<=n,(i for i in range(100))))[-1]
    c=list(i.takewhile(lambda i:6**i<=n,(i for i in range(100))))[-1]
    nb=n-9**b
    nc=n-6**c
    if nb<nc:
        n=nb
    else:
        n=nc
    ans+=1
    if n==0:
        break
print(ans)