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.BufferedReader;
import java.text.DecimalFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.io.*;

public class abc {
	static PrintWriter pw;

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

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

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

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

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}

	}

	public static long gcd(long a, long b) {
		return b == 0 ? a : gcd(b, a % b);
	}

	public static boolean isPrime(long n) {
		if (n == 2)
			return true;
		long i = 2;
		while (i * i <= n) {
			if (n % i == 0)
				return false;
			i++;
		}
		return true;
	}

	public static long[] remove(long n) {
		long res[] = new long[1000000000];
		long rese = 0;
		int i = 0;
		while (n > 0) {
			long dig = n % 10;
			n = n / 10;
			if (dig > 0) {
				rese = dig;
				res[i++] = rese;
			}
		}
		return res;
	}

	static int ceil(int x, int y) {
		return (x % y == 0 ? x / y : (x / y + 1));
	}

	static long ceil(long x, long y) {
		return (x % y == 0 ? x / y : (x / y + 1));
	}

	static int max(int x, int y) {
		return Math.max(x, y);
	}

	static int min(int x, int y) {
		return Math.min(x, y);
	}

	static int abs(int x) {
		return Math.abs(x);
	}

	static long abs(long x) {
		return Math.abs(x);
	}

	static int log2(int N) {
		int result = (int) (Math.log(N) / Math.log(2));
		return result;
	}

	static long max(long x, long y) {
		return Math.max(x, y);
	}

	static long min(long x, long y) {
		return Math.min(x, y);
	}

	public static class pair {
		int x;
		int y;

		public pair(int a, int b) {
			x = a;
			y = b;
		}
	}

	public static class Comp implements Comparator<pair> {
		public int compare(pair a, pair b) {
			if (a.x != b.x) {
				return a.x - b.x;
			} else {
				return a.y - b.y;
			}
		}
	}

	public static void extract(ArrayList<Integer> ar, int k, int d) {
		int c = 0;
		for (int i = 1; i < k; i++) {
			int x = 0;
			boolean dm = false;
			while (x > 0) {
				long dig = x % 10;
				x = x / 10;
				if (dig == d) {
					dm = true;
					break;
				}
			}
			if (dm)
				ar.add(i);
		}
	}

	public static void dfs(int index, boolean vis[], int a[], int b[], int n) {
		vis[index] = true;
		for (int i = 0; i < n; i++) {
			if (!vis[i] && (a[i] == a[index] || b[i] == b[index]))
				dfs(i, vis, a, b, n);
		}
	}

// counts the set(1) bit of a number
	public static long countSetBitsUtil(long x) {
		if (x <= 0)
			return 0;
		return (x % 2 == 0 ? 0 : 1) + countSetBitsUtil(x / 2);
	}

//tells whether a particular index has which bit of a number	
	public static int getIthBitsUtil(int x, int y) {
		return (x & (1 << y)) != 0 ? 1 : 0;
	}

	public static void swap(long x, long y) {
		x = x ^ y;
		y = y ^ x;
		x = x ^ y;
	}

	public static double decimalPlaces(double sum) {
		DecimalFormat df = new DecimalFormat("#.00");
		String angleFormated = df.format(sum);
		double fin = Double.parseDouble(angleFormated);
		return fin;
	}

//use collections.swap for swapping 
	static boolean isSubSequence(String str1, String str2, int m, int n) {
		int j = 0;

		for (int i = 0; i < n && j < m; i++)
			if (str1.charAt(j) == str2.charAt(i))
				j++;

		return (j == m);
	}

	static long[] sum(int k, long n) {
		long a[] = new long[k];
		int c = 0;
		while (n > 0) {
			a[c++] = n % 10;
			n = n / 10;
		}
		return a;
	}

	static long pow(long base, long power) {
		if (power == 0) {
			return 1;
		}
		long result = pow(base, power / 2);
		if (power % 2 == 1) {
			return result * result * base;
		}
		return result * result;
	}
	
	static int[] paisadomera(int n)
	{
		int a[]=new int[4];
		while(n%2==0)
		{
			a[1]++;
			n/=2;
		}
		while(n%3==0)
		{
			a[2]++;
			n/=3;
		}
		while(n%5==0)
		{
			a[3]++;
			n/=5;
		}
		a[0]=n;
		return a;
	}
	public static void main(String[] args) throws Exception {

		FastReader sc = new FastReader();
		pw = new PrintWriter(System.out);

		// use arraylist as it use the concept of dynamic table(amortized analysis)
		// Arrays.stream(array).forEach(a -> Arrays.fill(a, 0));
		/* List<Integer> l1 = new ArrayList<Integer>(); */
		int t = 1;
		while (t-- > 0) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			int arr1[]=paisadomera(a);
			int arr2[]=paisadomera(b);
			if(arr1[0]!=arr2[0])
				pw.println("-1");
			else
			pw.println(Math.abs(arr1[1]-arr2[1])+Math.abs(arr1[2]-arr2[2])+Math.abs(arr1[3]-arr2[3]));
		}
		pw.flush();
	}
}
