You have a fraction <image>. You need to find the first occurrence of digit c into decimal notation of the fraction after decimal point.

Input

The first contains three single positive integers a, b, c (1 ≤ a < b ≤ 105, 0 ≤ c ≤ 9).

Output

Print position of the first occurrence of digit c into the fraction. Positions are numbered from 1 after decimal point. It there is no such position, print -1.

Examples

Input

1 2 0


Output

2

Input

2 3 7


Output

-1

Note

The fraction in the first example has the following decimal notation: <image>. The first zero stands on second position.

The fraction in the second example has the following decimal notation: <image>. There is no digit 7 in decimal notation of the fraction. 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class A
{
	public static void main(String[] args) throws IOException
	{
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int ans = -1;
		int cnt = 1;
		boolean ok = false;
		for(int i=0;i<3000000;i++)
		{
			if(a == 0)
			{
				ans = cnt;
				if(c == 0)
					ok = true;
				break;
			}
			a*=10;
			int x = a / b;
			if(x == c)
			{
				ans = cnt;
				ok = true;
				break;
			}
			a -= x * b;
			cnt++;
		}
		if(!ok)
			System.out.println(-1);
		else
		{
			if(c == 0)
				System.out.println(ans);
			else
				System.out.println(ans);
		}
	}

	static class Scanner
	{
		StringTokenizer st;
		BufferedReader br;

		public Scanner(InputStream s)
		{
			br = new BufferedReader(new InputStreamReader(s));
		}

		public String next() throws IOException
		{
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

		public int nextInt() throws IOException
		{
			return Integer.parseInt(next());
		}

		public long nextLong() throws IOException
		{
			return Long.parseLong(next());
		}

		public String nextLine() throws IOException
		{
			return br.readLine();
		}

		public double nextDouble() throws IOException
		{
			return Double.parseDouble(next());
		}

		public boolean ready() throws IOException
		{
			return br.ready();
		}
	}
}
