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.*;
import java.math.BigDecimal;
import java.util.*;

public class Solution2 {

    private void solve() throws IOException {
        BigDecimal a = BigDecimal.valueOf(in.nextInt());
        BigDecimal b = BigDecimal.valueOf(in.nextInt());
        int c = in.nextInt();
        String s = a.divide(b, 10000, BigDecimal.ROUND_HALF_UP).toString();
        for (int j = 2; j < s.length() - 2; j++) {
            if (Integer.parseInt(s.substring(j, j + 1)) == c) {
                System.out.println(j - 1);
                return;
            }
        }
        System.out.println(-1);
    }


    private String filename = "";
    private PrintWriter out;
    MyScanner in;

    private void run() throws IOException {
        in = new MyScanner();
        out = new PrintWriter(System.out);
        solve();
        in.close();
        out.close();
    }

    private class MyScanner {
        private BufferedReader br;
        private StringTokenizer st;

        public MyScanner() throws IOException {
            this.br = new BufferedReader(new InputStreamReader(System.in));
        }

        public MyScanner(String fileTitle) throws IOException {
            this.br = new BufferedReader(new FileReader(fileTitle));
        }

        public String nextLine() throws IOException {
            String s = br.readLine();
            return s == null ? "-1" : s;
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens()) {
                String s = br.readLine();
                if (s == null) {
                    return "-1";
                }
                st = new StringTokenizer(s);
            }
            return st.nextToken();
        }

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

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

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

        public void close() throws IOException {
            this.br.close();
        }
    }

    public static void main(String[] args) throws IOException {
        Locale.setDefault(Locale.US);
        new Solution2().run();
    }
}
