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.*;

public class Main {


    void solve() throws IOException {
        int a = readInt();
        int b = readInt();
        a %= b;
        ArrayList<Integer> list = new ArrayList<>();
        for (int i =0;i<1000;i++){
            list.add(a/b);
            int ost = a%b;
            ost*=10;
            a=ost;
        }
        int c =readInt();
        for (int i=1;i<1000;i++){
            if(list.get(i)==c){
                out.println(i);
                return;
            }
        }
        out.println("-1");
    }

    int checkBit(int mask, int bit) {
        return (mask >> bit) & 1;
    }

    public static void main(String[] args) throws IOException {

        new Main().run();
    }

    boolean isLower(char a) {
        return ((int) a) >= 97 ? true : false;
    }

    int INF = Integer.MAX_VALUE / 10;

    int[][] STEPS = {{0, 1}, {1, 0}, {-1, 0}, {0, -1}};

    BufferedReader in;
    PrintWriter out;
    StringTokenizer tok;
    Random rnd = new Random();
    static final boolean ONLINE_JUDGE = System.getProperty("ONLINE_JUDGE") != null;

    Main() throws FileNotFoundException {

        try {
            in = new BufferedReader(new FileReader("input.txt"));
            out = new PrintWriter("output.txt");
        } catch (Exception e) {
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);
        }

        tok = new StringTokenizer("");
    }

    long checkBit(long mask, int bit) {
        return (mask >> bit) & 1;
    }

    void run() throws IOException {
        solve();
        out.close();
    }

    char varChar;
    int varInt, varInt1, varInt2;
    long varLong;

    long sqrt(long m) {
        long l = 0;
        long r = m;
        long answer = 0;
        long mid = 0;
        while (l <= r) {
            mid = (l + r) / 2;
            if (mid * mid <= m) {
                answer = mid;
                l = mid + 1;
            } else r = mid - 1;
        }
        return answer;
    }

    int countPow(int m, int n) {
        varInt = 0;
        while (m % n == 0 && m > 0) {
            varInt++;
            m /= n;
        }
        return varInt;
    }

    long binPow(long a, long b) {
        if (b == 0) {
            return 1;
        }
        if (b % 2 == 1) {
            return a * binPow(a, b - 1);
        } else {
            varLong = binPow(a, b / 2);
            return varLong * varLong;
        }

    }

    int gcd(int a, int b) {
        return b == 0 ? a : gcd(b, a % b);
    }

    long pow(long x, long k) {
        varLong = 1;
        for (int i = 0; i < k; ++i) {
            varLong *= x;
        }
        return varLong;
    }

    class Fenwik {
        private long[] t;
        private int length;

        Fenwik(int[] a) {
            this.length = a.length + 100;
            this.t = new long[length];
            for (int i = 0; i < a.length; ++i) {
                this.inc(i, a[i]);
            }
        }

        void inc(int i, int delta) {
            for (; i < this.length; i = i | (i + 1)) {
                this.t[i] += delta;
            }
        }

        long getSum(int r) {
            long sum = 0;

            for (; r >= 0; r = (r & (r + 1)) - 1) {
                sum += this.t[r];
            }

            return sum;
        }

    }

    // ////////////////////////////////////////////////////////////////////

    String delimiter = " ";

    String readLine() throws IOException {
        return in.readLine();
    }

    String readString() throws IOException {
        while (!tok.hasMoreTokens()) {
            String nextLine = readLine();
            if (null == nextLine)
                return null;

            tok = new StringTokenizer(nextLine);
        }

        return tok.nextToken(delimiter);
    }

    int readInt() throws IOException {
        return Integer.parseInt(readString());
    }

    long readLong() throws IOException {
        return Long.parseLong(readString());
    }

    double readDouble() throws IOException {
        return Double.parseDouble(readString());
    }

    int[] readIntArray(int b) {
        int a[] = new int[b];
        for (int i = 0; i < b; i++) {
            try {
                a[i] = readInt();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return a;
    }

    int[] readSortedIntArray(int size) throws IOException {
        Integer[] array = new Integer[size];

        for (int index = 0; index < size; ++index) {
            array[index] = readInt();
        }
        Arrays.sort(array);

        int[] sortedArray = new int[size];
        for (int index = 0; index < size; ++index) {
            sortedArray[index] = array[index];
        }

        return sortedArray;
    }

    int[] sortedIntArray(int size, int[] array) throws IOException {
        for (int index = 0; index < size; ++index) {
            array[index] = readInt();
        }
        Arrays.sort(array);

        int[] sortedArray = new int[size];
        for (int index = 0; index < size; ++index) {
            sortedArray[index] = array[index];
        }

        return sortedArray;
    }

    int minInt(int... values) {
        int min = Integer.MAX_VALUE;
        for (int value : values) {
            min = Math.min(min, value);
        }
        return min;
    }

    int maxInt(int... values) {
        int max = Integer.MIN_VALUE;
        for (int value : values) {
            max = Math.max(max, value);
        }
        return max;
    }

    long minLong(long... values) {
        long min = Long.MAX_VALUE;
        for (long value : values) {
            min = Math.min(min, value);
        }
        return min;
    }

    long maxLong(long... values) {
        long max = Long.MIN_VALUE;
        for (long value : values) {
            max = Math.max(max, value);
        }
        return max;
    }

    boolean checkIndex(int index, int size) {
        return (0 <= index && index < size);
    }

    int abs(int a) {
        return Math.abs(a);
    }
}