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.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.InputMismatchException;
import java.util.StringTokenizer;

public class CodeC {
  private static final boolean IN_DEBUG = true;

  static final SuperWriter sw = new SuperWriter(System.out);

  static int[] divisors = {2, 3, 5};

  static int[] count(int n) {
    int[] answer = new int[divisors.length + 1];
    for (int i = 0; i < divisors.length; i++) {
      while (n % divisors[i] == 0) {
        answer[i]++;
        n /= divisors[i];
      }
    }
    answer[3] = n;
    return answer;
  }

  public static void main(String[] args) {
    Scanner sc = new SuperScanner();
    int a = sc.nextInt();
    int b = sc.nextInt();
    int[] countA = count(a);
    int[] countB = count(b);
    if (countA[3] == countB[3]) {
      int total = 0;
      for (int i = 0; i < countA.length; i++) {
        total += Math.abs(countA[i] - countB[i]);
      }
      sw.printLine(total);
    } else {
      sw.printLine(-1);
    }
  }

  static class SuperScanner extends Scanner {
    private InputStream stream;
    private byte[] buf = new byte[8096];
    private int curChar;
    private int numChars;

    public SuperScanner() {
        this.stream = System.in;
    }

    public int read() {
        if (numChars == -1)
            throw new InputMismatchException();
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                throw new InputMismatchException();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }
    
    public static boolean isWhitespace(int c) {
      return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }
    
    private final StringBuilder sb = new StringBuilder();
    
    @Override
    public String next() {
      int c = read();
      while (isWhitespace(c)) {
          if (c == -1) {
            return null;
          }
          c = read();
      }
      sb.setLength(0);
      do {
          sb.append((char) c);
          c = read();
      } while (!isWhitespace(c));
      return sb.toString();
    }

    @Override
    public int nextInt() {
        int c = read();
        while (isWhitespace(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res = (res << 3) + (res << 1);
            res += c - '0';
            c = read();
        } while (!isWhitespace(c));
        return res * sgn;
    }

    @Override
    public long nextLong() {
        int c = read();
        while (isWhitespace(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        long res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res = (res << 3) + (res << 1);
            res += c - '0';
            c = read();
        } while (!isWhitespace(c));
        return res * sgn;
    }
  }
  
  static class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");

    public String nextLine() {
      try {
        return br.readLine();
      } catch (Exception e) {
        throw (new RuntimeException());
      }
    }

    public int nextIntOrQuit() {
      Integer n = nextInteger();
      if (n == null) {
        sw.close();
        System.exit(0);
      }
      return n.intValue();
    }

    public String next() {
      while (!st.hasMoreTokens()) {
        String l = nextLine();
        if (l == null)
          return null;
        st = new StringTokenizer(l);
      }
      return st.nextToken();
    }

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

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

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

    public int[] nextIntArray(int n) {
      int[] res = new int[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextInt();
      return res;
    }

    public long[] nextLongArray(int n) {
      long[] res = new long[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextLong();
      return res;
    }

    public double[] nextDoubleArray(int n) {
      double[] res = new double[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextDouble();
      return res;
    }

    public void sortIntArray(int[] array) {
      Integer[] vals = new Integer[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public void sortLongArray(long[] array) {
      Long[] vals = new Long[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public void sortDoubleArray(double[] array) {
      Double[] vals = new Double[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public String[] nextStringArray(int n) {
      String[] vals = new String[n];
      for (int i = 0; i < n; i++)
        vals[i] = next();
      return vals;
    }

    public Integer nextInteger() {
      String s = next();
      if (s == null)
        return null;
      return Integer.parseInt(s);
    }

    public int[][] nextIntMatrix(int n, int m) {
      int[][] ans = new int[n][];
      for (int i = 0; i < n; i++)
        ans[i] = nextIntArray(m);
      return ans;
    }

    public char[][] nextGrid(int r) {
      char[][] grid = new char[r][];
      for (int i = 0; i < r; i++)
        grid[i] = next().toCharArray();
      return grid;
    }

    public static <T> T fill(T arreglo, int val) {
      if (arreglo instanceof Object[]) {
        Object[] a = (Object[]) arreglo;
        for (Object x : a)
          fill(x, val);
      } else if (arreglo instanceof int[])
        Arrays.fill((int[]) arreglo, val);
      else if (arreglo instanceof double[])
        Arrays.fill((double[]) arreglo, val);
      else if (arreglo instanceof long[])
        Arrays.fill((long[]) arreglo, val);
      return arreglo;
    }

    public <T> T[] nextObjectArray(Class<T> clazz, int size) {
      @SuppressWarnings("unchecked")
      T[] result = (T[]) java.lang.reflect.Array.newInstance(clazz, size);
      for (int c = 0; c < 3; c++) {
        Constructor<T> constructor;
        try {
          if (c == 0)
            constructor = clazz.getDeclaredConstructor(Scanner.class,
                Integer.TYPE);
          else if (c == 1)
            constructor = clazz.getDeclaredConstructor(Scanner.class);
          else
            constructor = clazz.getDeclaredConstructor();
        } catch (Exception e) {
          continue;
        }
        try {
          for (int i = 0; i < result.length; i++) {
            if (c == 0)
              result[i] = constructor.newInstance(this, i);
            else if (c == 1)
              result[i] = constructor.newInstance(this);
            else
              result[i] = constructor.newInstance();
          }
        } catch (Exception e) {
          throw new RuntimeException(e);
        }
        return result;
      }
      throw new RuntimeException("Constructor not found");
    }

    public Collection<Integer> wrap(int[] as) {
      ArrayList<Integer> ans = new ArrayList<Integer>();
      for (int i : as)
        ans.add(i);
      return ans;
    }

    public int[] unwrap(Collection<Integer> collection) {
      int[] vals = new int[collection.size()];
      int index = 0;
      for (int i : collection)
        vals[index++] = i;
      return vals;
    }
  }

  static class SuperWriter {

    private final PrintWriter writer;

    public SuperWriter(OutputStream outputStream) {
      writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public SuperWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void close() {
        writer.flush();
        writer.close();
    }

    public void printLine(String line) {
      writer.println(line);
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public void printLine(int... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public void printLine(long... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public void printLine(double... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public void printLine(int prec, double... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        String precision = "%." + prec + "f";
        writer.print(String.format(precision, vals[0]).replace(',', '.'));
        precision = " " + precision;
        for (int i = 1; i < vals.length; i++)
          writer.print(String.format(precision, vals[i]).replace(',', '.'));
        writer.println();
      }
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public <E> void printLine(Collection<E> vals) {
      if (vals.size() == 0) {
        writer.println();
      } else {
        int i = 0;
        for (E val : vals) {
          if (i++ == 0) {
            writer.print(val.toString());
          } else {
            writer.print(" ".concat(val.toString()));
          }
        }
        writer.println();
      }
      if (IN_DEBUG) {
        writer.flush();
      }
    }

    public void print(String value) {
      writer.print(value);
      if (IN_DEBUG) {
        writer.flush();
      }
    }
  }

}

