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.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.StringTokenizer;

public class A implements Runnable {
	static String Y = "YES", N = "NO";
	static long inf = (long) 1e18;

	public static void main(String[] args) {
		new Thread(null, new A(), "Solver", 1L << 26).start();
	}

	private FastScanner scan;
	private PrintWriter out;

	public A() {
		scan = new FastScanner(System.in);
		out = new PrintWriter(System.out);
	}

	public void run() {
		try {
			solve();
			out.close();
		} catch (Exception e) {
			e.printStackTrace();
			System.out.println(1 / 0);
		}
	}

	static long ceilDiv(long n, long d) {
		if (n < 0 != d < 0) {
			return (n / d) - (n % d == 0 ? 0 : 1);
		}
		return (n / d) + (n % d == 0 ? 0 : 1);
	}

	void solve() throws IOException {
		int a = scan.nextInt(), b = scan.nextInt();
		int[] arr1 = new int[3];
		int[] arr2 = new int[3];
		
		int a2 = a, b2 = b;
		while(a2 % 2 == 0) {
			a2 /= 2;
			arr1[0]++;
		}
		while(a2 % 3 == 0) {
			a2 /= 3;
			arr1[1]++;
		}
		while(a2 % 5 == 0) {
			a2 /= 5;
			arr1[2]++;
		}

		while(b2 % 2 == 0) {
			b2 /= 2;
			arr2[0]++;
		}
		while(b2 % 3 == 0) {
			b2 /= 3;
			arr2[1]++;
		}
		while(b2 % 5 == 0) {
			b2 /= 5;
			arr2[2]++;
		}
		
		
		int moves = Math.abs(arr1[0] - arr2[0]) + Math.abs(arr1[1] - arr2[1]) + Math.abs(arr1[2] - arr2[2]);
		if(a2 == b2) {
			out.println(moves);
		} else {
			out.println(-1);
		}
		
	}

	void print(int[] arr) {
		for (int i = 0; i < arr.length; i++) {
			out.print(arr[i]);
			if (i == arr.length - 1)
				out.println();
			else
				out.print(" ");
		}

	}

	static class Pair implements Comparable<Pair> {
		long a, b;

		public Pair(long a, long b) {
			this.a = a;
			this.b = b;
		}

		@Override
		public int compareTo(Pair o) {
			if (a == o.a)
				return Long.compare(b, o.b);
			return Long.compare(a, o.a);
		}
	}

	static long max(long... ls) {
		long max = ls[0];
		for (long l : ls) {
			if (l > max)
				max = l;
		}
		return max;
	}

	static int max(int... ls) {
		int max = ls[0];
		for (int l : ls) {
			if (l > max)
				max = l;
		}
		return max;
	}

	static double max(double... ls) {
		double max = ls[0];
		for (double l : ls) {
			if (l > max)
				max = l;
		}
		return max;
	}

	static long min(long... ls) {
		long min = ls[0];
		for (long l : ls) {
			if (l < min)
				min = l;
		}
		return min;
	}

	static double min(double... ls) {
		double min = ls[0];
		for (double l : ls) {
			if (l < min)
				min = l;
		}
		return min;
	}

	static int min(int... ls) {
		int min = ls[0];
		for (int l : ls) {
			if (l < min)
				min = l;
		}
		return min;
	}

	static void yes(boolean a) {
		System.out.println(a ? Y : N);
	}

	static long gcd(long a, long b) {
		if (b == 0)
			return a;
		return gcd(b, a % b);
	}

	static class FastScanner {
		BufferedReader br;
		StringTokenizer st;

		public FastScanner(InputStream in) {
			br = new BufferedReader(new InputStreamReader(in));
			st = new StringTokenizer("");
		}

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

		public String next() throws IOException {
			while (!st.hasMoreTokens()) {
				st = new StringTokenizer(br.readLine());
			}
			return st.nextToken();
		}
	}

	class BPM {
		private Dinics d;
		private int leftCount;
		private int rightCount;

		public BPM(int leftCount, int rightCount) {
			this.leftCount = leftCount;
			this.rightCount = rightCount;
			this.d = new Dinics(leftCount + rightCount + 2, 0, leftCount + rightCount + 1);
			for (int i = 1; i <= leftCount; i++) {
				d.addEdge(d.s, i, 1);
			}
			for (int i = leftCount + 1; i <= leftCount + rightCount; i++) {
				d.addEdge(i, d.t, 1);
			}
		}

		public void addMatching(int left, int right) {
			d.addEdge(1 + left, 1 + leftCount + right, 1);
		}

		public int[] getMatchings() {
			this.d.calculateFlow();
			int[] answer = new int[leftCount];
			Arrays.fill(answer, -1);
			for (edge e : this.d.e) {
				if (e.a == d.s || e.b == d.t)
					continue;
				if (e.flow != 1)
					continue;
				answer[e.a - 1] = e.b - (leftCount + 1);
			}
			return answer;
		}
	}

	class Dinics {
		public static final int INF = 1000000000;

		public Dinics(int n, int s, int t) {
			this.n = n;
			this.g = new ArrayList[n];
			this.s = s;
			this.t = t;
			this.q = new int[n];
			this.d = new int[n];
			this.ptr = new int[n];
			this.intd = new int[n];
			for (int i = 0; i < n; i++)
				g[i] = new ArrayList<Integer>();
		}

		int n, s, t;
		int[] intd;
		int[] ptr;
		int[] d;
		int[] q;
		ArrayList<edge> e = new ArrayList<edge>();
		ArrayList<Integer>[] g;

		void addEdge(int a, int b, int cap) {
			edge e1 = new edge(a, b, cap, 0);
			edge e2 = new edge(b, a, 0, 0);
			g[a].add((int) e.size());
			e.add(e1);
			g[b].add((int) e.size());
			e.add(e2);
		}

		boolean bfs() {
			int qh = 0, qt = 0;
			q[qt++] = s;
			Arrays.fill(d, -1);
			d[s] = 0;
			while (qh < qt && d[t] == -1) {
				int v = q[qh++];
				for (int i = 0; i < g[v].size(); ++i) {
					int id = g[v].get(i), to = e.get(id).b;
					if (d[to] == -1 && e.get(id).flow < e.get(id).cap) {
						q[qt++] = to;
						d[to] = d[v] + 1;
					}
				}
			}
			return d[t] != -1;
		}

		int dfs(int v, int flow) {
			if (flow == 0)
				return 0;
			if (v == t)
				return flow;
			for (; ptr[v] < (int) g[v].size(); ++ptr[v]) {
				int id = g[v].get(ptr[v]), to = e.get(id).b;
				if (d[to] != d[v] + 1)
					continue;
				int pushed = dfs(to, Math.min(flow, e.get(id).cap - e.get(id).flow));
				if (pushed != 0) {
					e.get(id).flow += pushed;
					e.get(id ^ 1).flow -= pushed;
					return pushed;
				}
			}
			return 0;
		}

		public int calculateFlow() {
			int flow = 0;
			for (;;) {
				if (!bfs())
					break;
				Arrays.fill(ptr, 0);
				int pushed;
				while ((pushed = dfs(s, INF)) != 0)
					flow += pushed;
			}
			return flow;
		}

	}

	static class edge {
		int a, b, cap, flow;

		public edge(int a, int b, int cap, int flow) {
			this.a = a;
			this.b = b;
			this.cap = cap;
			this.flow = flow;
		}
	}
}