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 Java7 (OpenJDK 1.7.0) (judge verdict: Wrong Answer)

import java.util.Scanner;
 
public class Main {
 
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		int N = sc.nextInt();
		
		int count = 0;
		
		int[] A = {9, 6, 1};
		
		for (int i = 0; i < 3; ++i) {
			while (N > 0) {
				int x = calc(N, A[i]);
				if (x > 0) {
					count++;
					N -= Math.pow(A[i], x);
				} else {
					break;
				}
			}
		}
		
		System.out.println(count);
	}
	
	private static int calc(int n, int a) {
		if (a == 1) {
			return 1;
		}
		int i = 1;
		while (true) {
			if (n < a * i) {
				return i - 1; 
			} else {
				i++;
			}
		}
	}
}