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.util.StringTokenizer;

public class Solution {

    public static void solve(InputReader in, PrintWriter out, DebugWriter debug) throws IOException {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        for (int i = 0; i < 100000; i++) {
            a *= 10;
            if (a/b == c) {
                out.println(i + 1);
                return;
            }
            a = a % b;
            debug.println(a);
        }

        out.println(-1);
    }

    public static final String NAME = "";

    public static void main(String[] args) throws IOException{
        InputReader in;
        PrintWriter out;
        DebugWriter debug;

        if (args.length > 0 && args[0].equals("file")) {
            in = new InputReader(new BufferedReader(new FileReader("input.txt")));
            out = new PrintWriter(new FileWriter("output.txt"));
            debug = new DebugWriter(true);

            int sampleNumber = 1;
            do {
                String nextSample = "Sample #" + sampleNumber++ + ": ";
                out.println(nextSample);
                debug.println(nextSample);

                solve(in, out, debug);

                out.println("");
                debug.println("");
            } while (in.reader.readLine() != null);
        } else {
            if (NAME.length() > 0) {
                in = new InputReader(new BufferedReader(new FileReader(NAME + ".in")));
                out = new PrintWriter(new FileWriter(NAME + ".out"));
            } else {
                in = new InputReader(new BufferedReader(new InputStreamReader(System.in)));
                out = new PrintWriter(new OutputStreamWriter(System.out));
            }

            debug = new DebugWriter(false);
            solve(in, out, debug);
        }

        in.reader.close();
        out.close();
    }

    public static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public InputReader(BufferedReader reader) {
            this.reader = reader;
            tokenizer = null;
        }

        public String next() throws IOException{
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                tokenizer = new StringTokenizer(reader.readLine());
            }

            return tokenizer.nextToken();
        }

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

        public int[] nextIntArray(int n) throws IOException{
            int[] array = new int[n];
            for (int i=0; i<n; i++){
                array[i] = nextInt();
            }

            return array;
        }
    }

    public static class DebugWriter {
        public boolean enable;

        public DebugWriter(boolean enable){
            this.enable = enable;
        }

        public void print(Object o){
            if (enable) System.out.print(o);
        }

        public void println(Object o){
            if (enable) System.out.println(o);
        }
    }

}