Two little greedy bears have found two pieces of cheese in the forest of weight a and b grams, correspondingly. The bears are so greedy that they are ready to fight for the larger piece. That's where the fox comes in and starts the dialog: "Little bears, wait a little, I want to make your pieces equal" "Come off it fox, how are you going to do that?", the curious bears asked. "It's easy", said the fox. "If the mass of a certain piece is divisible by two, then I can eat exactly a half of the piece. If the mass of a certain piece is divisible by three, then I can eat exactly two-thirds, and if the mass is divisible by five, then I can eat four-fifths. I'll eat a little here and there and make the pieces equal". 

The little bears realize that the fox's proposal contains a catch. But at the same time they realize that they can not make the two pieces equal themselves. So they agreed to her proposal, but on one condition: the fox should make the pieces equal as quickly as possible. Find the minimum number of operations the fox needs to make pieces equal.

Input

The first line contains two space-separated integers a and b (1 ≤ a, b ≤ 109). 

Output

If the fox is lying to the little bears and it is impossible to make the pieces equal, print -1. Otherwise, print the required minimum number of operations. If the pieces of the cheese are initially equal, the required number is 0.

Examples

Input

15 20


Output

3


Input

14 8


Output

-1


Input

6 6


Output

0
import java.io.*;
import java.util.*;
import java.math.*;

public class ProducingSnow {
    static Scanner sc = new Scanner(System.in);
    static PrintWriter pw = new PrintWriter(System.out), pw2 = new PrintWriter(System.out);
    static boolean check(int x,int y){
        while(x%2==0)
            x/=2;
        while(x%3==0)
            x/=3;
        while(x%5==0)
            x/=5;
        while(y%2==0)
            y/=2;
        while(y%3==0)
            y/=3;
        while(y%5==0)
            y/=5;
        return x==y;
    }
    static int get(int x,int div){
        int temp=0;
        while(x%div==0){
            x/=div;
            temp++;
        }
        return temp;
    }
    public static void main(String[] args) throws IOException {
        int x=sc.nextInt(),y=sc.nextInt();
        if(check(x,y)) {
            int powTwo2 =get(x,2),powThree2 =get(x,3), powFive2 =get(x,5);
            int powTwo5=get(y,2),powThree5=get(y,3),powFive5=get(y,5);
            System.out.println(Math.abs(powFive2-powFive5)+Math.abs(powThree2-powThree5)+Math.abs(powTwo2-powTwo5));
        }else
            System.out.println(-1);
    }

    public static <E> void print2D(E[][] arr) {
        for (int i = 0; i < arr.length; i++) {
            for (int j = 0; j < arr[i].length; j++) {
                pw.println(arr[i][j]);
            }
        }
    }

    public static int digitSum(String s) {
        int toReturn = 0;
        for (int i = 0; i < s.length(); i++) toReturn += Integer.parseInt(s.charAt(i) + " ");
        return toReturn;
    }

    public static boolean isPrime(long n) {
        if (n <= 1)
            return false;
        if (n <= 3)
            return true;

        if (n % 2 == 0 || n % 3 == 0)
            return false;

        for (long i = 5; i * i <= n; i = i + 6)
            if (n % i == 0 || n % (i + 2) == 0)
                return false;
        return true;
    }

    public static long pow(long a, long pow) {
        return pow == 0 ? 1 : pow % 2 == 0 ? pow(a * a, pow >> 1) : a * pow(a * a, pow >> 1);
    }

    public static long sumNum(long a) {
        return a * (a + 1) / 2;
    }

    public static int gcd(int n1, int n2) {
        return n2 == 0 ? n1 : gcd(n2, n1 % n2);
    }

    public static long factorial(long a) {
        return a == 0 || a == 1 ? 1 : a * factorial(a - 1);
    }

    public static void sort(int arr[]) {
        shuffle(arr);
        Arrays.sort(arr);
    }

    public static void shuffle(int arr[]) {
        Random rnd = new Random();
        for (int i = arr.length - 1; i > 0; i--) {
            int index = rnd.nextInt(i + 1);
            int temp = arr[index];
            arr[index] = arr[i];
            arr[i] = temp;
        }
    }

    public static Double[] solveQuadratic(double a, double b, double c) {
        double result = (b * b) - 4.0 * a * c;
        double r1;
        if (result > 0.0) {
            r1 = ((double) (-b) + Math.pow(result, 0.5)) / (2.0 * a);
            double r2 = ((double) (-b) - Math.pow(result, 0.5)) / (2.0 * a);
            return new Double[]{r1, r2};
        } else if (result == 0.0) {
            r1 = (double) (-b) / (2.0 * a);
            return new Double[]{r1, r1};
        } else {
            return new Double[]{null, null};
        }
    }

    static class Scanner {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(FileReader r) {
            br = new BufferedReader(r);
        }

        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 {
            String x = next();
            StringBuilder sb = new StringBuilder("0");
            double res = 0, f = 1;
            boolean dec = false, neg = false;
            int start = 0;
            if (x.charAt(0) == '-') {
                neg = true;
                start++;
            }
            for (int i = start; i < x.length(); i++)
                if (x.charAt(i) == '.') {
                    res = Long.parseLong(sb.toString());
                    sb = new StringBuilder("0");
                    dec = true;
                } else {
                    sb.append(x.charAt(i));
                    if (dec)
                        f *= 10;
                }
            res += Long.parseLong(sb.toString()) / f;
            return res * (neg ? -1 : 1);
        }

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

    static class pair<E1, E2> implements Comparable<pair> {
        E1 x;
        E2 y;

        pair(E1 x, E2 y) {
            this.x = x;
            this.y = y;
        }

        @Override
        public int compareTo(pair o) {
            return x.equals(o.x) ? (Integer) y - (Integer) o.y : (Integer) x - (Integer) o.x;
        }

        @Override
        public String toString() {
            return x + " " + y;
        }

        public double pointDis(pair p1) {
            return Math.sqrt(((Integer) y - (Integer) p1.y) * ((Integer) y - (Integer) p1.y) + ((Integer) x - (Integer) p1.x) * ((Integer) x - (Integer) p1.x));
        }
    }

}
