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.InputStreamReader;
import java.util.*;

public class Codeforces {

    private static final Scanner sc = new Scanner(System.in);
    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    private static final long MOD = (long) (1e9 + 7);

    public static int[] LPS(String p){
        int[] lps = new int[p.length()];

        int i=1;
        int j=0;
        while (i < p.length()){
            if (p.charAt(i) == p.charAt(j)){
                lps[i] = j+1;
                i++;
                j++;
            }
            else{
                if (j == 0){
                    lps[i] = 0;
                    i++;
                }
                else{
                    j = lps[j-1];
                }
            }
        }
        return lps;
    }

    public static void KMP(String text,String pattern){
        int[] lps = LPS(pattern);
        int i = 0;
        int j = 0;
        ArrayList<Integer> matches = new ArrayList<>();
        while (i < text.length()){
            if (text.charAt(i) == pattern.charAt(j)){
                i++;
                j++;
            }
            else{
                if (j != 0){
                    j = lps[j-1];
                }
                else {
                    i++;
                }
            }
            if (j == pattern.length()) {
                matches.add(i - j);
                j = lps[j-1];
            }
        }
        for (int x : matches){
            System.out.println("Match at : " + x);
        }
    }

    private static class SegmentTree{
        private long[] st;
        private int size;
        private int n;
        private long[] a;
        SegmentTree(long[] a,int n){
            this.size = 4*n;
            this.n = n;
            this.a = a;
            st = new long[size];
            //Arrays.fill(st,Integer.MIN_VALUE);
            buildSegmentTree(0,0,n-1);
            //printSegmentTree();
        }
        public long buildSegmentTree(int index,int l,int r){
            if (l == r){
                st[index] = a[l];
                return a[l];
            }
            int mid = (r+l) >> 1;
            return st[index] = buildSegmentTree(2*index+1,l,mid) + buildSegmentTree(2*index+2,mid+1,r);
        }
        public void printSegmentTree(){
            for (long x : st){
                System.out.print(x + " ");
            }
            System.out.println();
        }
        public long query(int ql,int qr){
            return getQuery(0,0,n-1,ql-1,qr-1);
        }
        private long getQuery(int index,int sl,int sr,int ql,int qr){
            //System.out.println("#" + index);
            if (qr < sl || ql > sr)
                return 0;
            if (ql <= sl && qr >= sr)
                return st[index];
            int mid = (sr + sl) >> 1;
            return getQuery(2*index+1,sl,mid,ql,qr) + getQuery(2*index+2,mid+1,sr,ql,qr);
        }
        public void update(int i,long newVal){
            //long diff = newVal - a[i];
            a[i] = newVal;
            updateSegmentTree(0,i,0,n-1,newVal);
        }
        private void updateSegmentTree(int index,int i,int sl,int sr,long diff){
            if (sl == sr){
                st[index] = diff;
                return;
            }
            int mid = (sl + sr) >> 1;
            if (i <= mid)
                updateSegmentTree(2*index+1,i,sl,mid,diff);
            else
                updateSegmentTree(2*index+2,i,mid+1,sr,diff);
            st[index] = st[2*index+1] + st[2*index+2];
        }
    }

    public static class Pair<T1,T2>{
        T1 first;
        T2 second;
        Pair(T1 a,T2 b){
            this.first = a;
            this.second = b;
        }

        @Override
        public String toString() {
            return "[" + first + ", " + second + "]";
        }
    }

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

    static int highestPowerOf2(int n) {
        int p = (int)(Math.log(n) /
                Math.log(2));
        return (int)Math.pow(2, p);
    }

    public static int binSearch(long[] a,long x){
        int l = 0;
        int r = a.length - 1;
        while (l <= r){
            int mid = l + (r-l)/2;
            if (a[mid]==x)
                return 1;
            else if (a[mid] < x)
                l = mid+1;
            else
                r = mid-1;
        }
        return -1;
    }

    public static int upperBound(long[] arr,long key){
        int start=0;int end=arr.length-1;
        int idx=-1;
        int mid;
        while(start<=end){
            int i=(start+end)/2;
            if(arr[i]<key){
                start=i+1;
            }
            else if(arr[i]>key){
                end=i-1;
            }
            else{
                idx=i;
                start=i+1;
            }
        }

        return idx;    }

    public static int lowerBound(long[] arr,long key){
        int start=0;int end=arr.length-1;
        int idx=-1;
        int mid;
        while(start<=end){
            int i=(start+end)/2;
            if(arr[i]<key){
                start=i+1;
            }
            else if(arr[i]>key){
                end=i-1;
            }
            else{
                idx=i;
                end=i-1;
            }
        }
        return idx;
    }

    public static int searchInsert(long[] nums, long target) {
        int s=0,e=nums.length-1;
        int mid;
        if(target<nums[0]){
            return 0;
        }
        while(s<=e){
            mid=(s+e)/2;
            if(nums[mid]>target){
                e=mid-1;
            }
            else if(nums[mid]==target){
                return mid;
            }
            else{
                s=mid+1;
            }
        }
        return s;
    }

    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 <= Math.sqrt(n); i = i + 6)
            if (n % i == 0 || n % (i + 2) == 0)
                return false;

        return true;
    }

    public static long fastExpo(long a,int n,int mod){
        if (n == 0)
            return 1;
        else{
            if ((n&1) == 1){
                long x = fastExpo(a,n/2,mod);
                return (((a*x)%mod)*x)%mod;
            }
            else{
                long x = fastExpo(a,n/2,mod);
                return (((x%mod)*(x%mod))%mod)%mod;
            }
        }
    }

    public static long modInverse(long n,int p){
        return fastExpo(n,p-2,p);
    }

    public static long nCr(int n,int r,long[] fact,int mod){
        long val =  (((fact[n] * modInverse(fact[r],mod))%mod)*modInverse(fact[n-r],mod))%mod;
        return val;
    }

    public static void factorial(long[] fact,int n,int mod){
        for (int i=1;i<=n;i++){
            fact[i] = (fact[i-1] * i)%mod;
        }
    }

    public static int log2(long val){
        return (int) Math.floor(Math.log(val)/Math.log(2));
    }

    public static boolean isSubSequence(String s,String t){
        int i = 0;
        int j = 0;
        while (i < s.length() && j < t.length()){
            if (s.charAt(i) == t.charAt(j))
                j++;
            i++;
        }
        return j == t.length();
    }

    public static long[] getValues(long x){
        long a2 = 0;
        long a3 = 0;
        long a5 = 0;
        while (x%2 == 0){
            a2++;
            x /= 2;
        }
        while (x%3 == 0){
            a3++;
            x /= 3;
        }
        while (x%5 == 0){
            a5++;
            x /= 5;
        }
        long[] ans = new long[]{x,a2,a3,a5};
        return ans;
    }
    public static void solve() throws IOException {
        long a = sc.nextLong();
        long b = sc.nextLong();
        long[] a1 = getValues(a);
        long[] b2 = getValues(b);

        if (a1[0] != b2[0]){
            System.out.println(-1);
            return;
        }
        long ans = Math.abs(a1[1] - b2[1]) + Math.abs(a1[2] - b2[2]) + Math.abs(a1[3] - b2[3]);
        System.out.println(ans);
    }
    public static void main(String[] args) throws IOException {
        int t;
//        t = sc.nextInt();
        t = 1;
        while (t-- > 0){
            solve();
        }
        System.gc();
    }
}

