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.math.BigInteger;
    			import java.util.*;
    				
    				
    				public class Practice {
    					private static InputStream stream;
    					private static byte[] buf = new byte[1024];
    					private static int curChar;
    					private static int numChars;
    					private static SpaceCharFilter filter;
    					private static PrintWriter pw;
    					private static long mod=1000000007;
    				
    				    public static void main(String[] args) {
    				    	InputReader(System.in);
    						pw = new PrintWriter(System.out); 
    				        new Thread(null ,new Runnable(){
    				           public void run(){
    				               try{
    				                   solve();//This is solution method
    				                   pw.close();
    				               } catch(Exception e){
    				                   e.printStackTrace();
    				               }
    				           }
    				       },"1",1<<26).start();
    				   }
    				    static long sort(int a[])
        		    	{  int n=a.length;
        		    		int b[]=new int[n];	
        		    		return mergeSort(a,b,0,n-1);}
        		    	static long mergeSort(int a[],int b[],long left,long right)
        		    	{ long c=0;if(left<right)
        		    	 {   long mid=left+(right-left)/2;
        		    		 c= mergeSort(a,b,left,mid);
        		    		 c+=mergeSort(a,b,mid+1,right);
        		    		 c+=merge(a,b,left,mid+1,right); }	
        		    		return c;	 }
        		    	static long merge(int a[],int  b[],long left,long mid,long right)
        		    	{long c=0;int i=(int)left;int j=(int)mid; int k=(int)left;
        		    	while(i<=(int)mid-1&&j<=(int)right)
        		    	{ if(a[i]>a[j]) {b[k++]=a[i++]; }
        		    	else	{ b[k++]=a[j++];c+=mid-i;}}
        		    	while (i <= (int)mid - 1)   b[k++] = a[i++]; 
        		    	while (j <= (int)right) b[k++] = a[j++];
        		    	for (i=(int)left; i <= (int)right; i++) 
        		    		a[i] = b[i];  return c;  }
        		    		    
    				    
    				    
    				    private static void solve() throws NumberFormatException, IOException
    				    {
    				    long a=nextLong();
    				    long b=nextLong();
    				    long gcd=gcd(a, b);
    				   long no_op=0;
    				   a/=gcd;
    				   b/=gcd;
    				    while(a>1){
    				    	if(a%2==0){
    				    	a/=2;
    				    	}
    				    	else if(a%3==0){
    				    		a/=3;
    				    		
    				    	}else if(a%5==0){
    				    		a/=5;
    				    			}else{
    				    		pw.println(-1);
    				    		return;
    				    	}
    				    	no_op++;
    				    }
    				    
    				    while(b>1){
    				    	if(b%2==0){
    				    	b/=2;
    				    	}
    				    	else if(b%3==0){
    				    		b/=3;
    				    		
    				    	}else if(b%5==0){
    				    		b/=5;
    				    		}else{
    				    		pw.println(-1);
    				    		return;
    				    	}
    				    	no_op++;
    				    }
    				    pw.print(no_op);
    				    }

    				     private static List<Integer> findFactors(int x){
    				         List<Integer> list = new ArrayList<>();

    				         for(int i =2; i<=Math.sqrt(x);i++){
    				             if(x%i == 0) {
    				                 list.add(i);
    				                 if(x/i != i) list.add(x/i);
    				             }
    				         }
    				         list.add(x);
    				         Collections.sort(list);
    				         return list;
    				     }

    				   
    					public static long pow(long n, long p) {
				    		if(p==0)
				    			return 1;
				    		if(p==1)
				    			return n;
				    		if(p%2==0){
				    			long temp=pow(n, p/2);
				    		return (temp*temp);
				    		}else{
				    			 	long temp=pow(n,p/2);
				    			 	temp=(temp*temp);
				    			 	return(temp*n);
				    			 	
				    		}
				    	}
    				    public static String reverseString(String s) {
    			    		StringBuilder sb = new StringBuilder(s);
    			    		sb.reverse();
    			    		return (sb.toString());
    			    	}
    				    private static BigInteger ncr(int n,int k){
    				    	if (k < 0 || k > n) return BigInteger.ZERO;
    				        if (n-k < k) k = n-k;
    			
    				        BigInteger x = BigInteger.ONE;
    				        for (int i = 1; i <= k; i++) {
    				            x = x.multiply(new BigInteger(""+(n-i+1)));
    				            x = x.divide(new BigInteger(""+i));
    				        }
    			
    				return x;
    				    }
    				    static long fact[];
    				private static void factmod(int n,int mod){
    					fact=new long[n+1];
    					fact[0]=1;
    					for(int i=1;i<=n;i++){
    						fact[i]=i*fact[i-1];
    						//fact[i]%=mod;
    				
    					}
    					
    				}
    				private static long phi(long n){
    					long ans=n;
    					if(n%2==0)
    						ans-=(ans/2);
    					while(n%2==0)
    					{
    						n/=2;
    						
    					}
    					for(int i=3;i*i<=n;i+=2){
    						if(n%i==0){
    						while(n%i==0){
    							n/=i;
    						}
    						ans-=(ans/i);
    						}
    					}
    					if(n>2)
    						ans-=(ans/n);
    					
    					return ans;
    				}
    				static long d,x,y;
    				static long modInverse(long A, long M)
    				{
    				extendedEuclid(A,M);
    				return (x%M+M)%M;    //x may be negative
    				}
    				static void extendedEuclid(long A, long B) {
    				if(B == 0) {
    				d = A;
    				x = 1;
    				y = 0;
    				}
    				else {
    				extendedEuclid(B, A%B);
    				long temp = x;
    				x = y;
    				y = temp - (A/B)*y;
    				}
    				}
    				static boolean prime[];
    				static int spf[];
    				public static void sieve(int n){
    					prime=new boolean[100001];
    					spf=new int[100001];
    					Arrays.fill(prime, true);
    				spf[2]=2;
    					for(int i=4;i<=100000;i+=2)
    					{
    						spf[i]=2;
    						prime[i]=false;
    					}
    				
    				for(int i=3;i*i<=100000;i+=2){
    					if(prime[i]){
    						spf[i]=i;
    						for(int j=2*i;j<=100000;j+=i){
    							
    							prime[j]=false;
    						if(spf[j]==0){
    							spf[j]=i;
    						}
    						}
    					}
    				}
    					
    				}
    				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 n, long p,long mod) {
    						if(p==0)
    							return 1;
    						if(p==1)
    							return n%mod;
    						if(p%2==0){
    							long temp=pow(n, p/2,mod);
    						return (temp*temp)%mod;
    						}else{
    							 	long temp=pow(n,p/2,mod);
    							 	temp=(temp*temp)%mod;
    							 	return(temp*n)%mod;
    							 	
    						}
    					}
    					public static long gcd(long x, long y) {
    						if (x == 0)
    							return y;
    						else
    							return gcd( y % x,x);
    					}
    					
    					
    					public static void InputReader(InputStream stream1) {
    						stream = stream1;
    					}
    				 
    					private static boolean isWhitespace(int c) {
    						return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    					}
    				 
    					private static boolean isEndOfLine(int c) {
    						return c == '\n' || c == '\r' || c == -1;
    					}
    				 
    					private static 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++];
    					}
    				 
    					private static int nextInt() {
    						int c = read();
    						while (isSpaceChar(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 *= 10;
    							res += c - '0';
    							c = read();
    						} while (!isSpaceChar(c));
    						return res * sgn;
    					}
    				 
    					private static long nextLong() {
    						int c = read();
    						while (isSpaceChar(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 *= 10;
    							res += c - '0';
    							c = read();
    						} while (!isSpaceChar(c));
    						return res * sgn;
    					}
    				 
    					private static String nextToken() {
    						int c = read();
    						while (isSpaceChar(c))
    							c = read();
    						StringBuilder res = new StringBuilder();
    						do {
    							res.appendCodePoint(c);
    							c = read();
    						} while (!isSpaceChar(c));
    						return res.toString();
    					}
    				 
    					private static String nextLine() {
    						int c = read();
    						while (isSpaceChar(c))
    							c = read();
    						StringBuilder res = new StringBuilder();
    						do {
    							res.appendCodePoint(c);
    							c = read();
    						} while (!isEndOfLine(c));
    						return res.toString();
    					}
    				 
    					private static int[] nextIntArray(int n) {
    						int[] arr = new int[n];
    						for (int i = 0; i < n; i++) {
    							arr[i] = nextInt();
    						}
    						return arr;
    					}
    				 
    					private static int[][] next2dArray(int n, int m) {
    						int[][] arr = new int[n][m];
    						for (int i = 0; i < n; i++) {
    							for (int j = 0; j < m; j++) {
    								arr[i][j] = nextInt();
    							}
    						}
    						return arr;
    					}
    					private static char[][] nextCharArray(int n,int m){
    						char [][]c=new char[n][m];
    						for(int i=0;i<n;i++){
    							String s=nextLine();
    							for(int j=0;j<s.length();j++){
    								c[i][j]=s.charAt(j);
    							}
    						}
    						return c;
    					}
    				 
    					private static long[] nextLongArray(int n) {
    						long[] arr = new long[n];
    						for (int i = 0; i < n; i++) {
    							arr[i] = nextLong();
    						}
    						return arr;
    					}
    				 
    					private static void pArray(int[] arr) {
    						for (int i = 0; i < arr.length; i++) {
    							pw.print(arr[i] + " ");
    						}
    						pw.println();
    						return;
    					}
    				 
    					private static void pArray(long[] arr) {
    						for (int i = 0; i < arr.length; i++) {
    							pw.print(arr[i] + " ");
    						}
    						pw.println();
    						return;
    					}
    				 
    					private static void pArray(boolean[] arr) {
    						for (int i = 0; i < arr.length; i++) {
    							pw.print(arr[i] + " ");
    						}
    						pw.println();
    						return;
    					}
    				 
    					private static boolean isSpaceChar(int c) {
    						if (filter != null)
    							return filter.isSpaceChar(c);
    						return isWhitespace(c);
    					}
    				 
    					private interface SpaceCharFilter {
    						public boolean isSpaceChar(int ch);
    					}
    				
    					
    				}	
    				
    				class Pair implements Comparable<Pair>{
    					
    					int x,y;
    					Pair(int x,int y){
    						
    						this.x=x;
    						this.y=y;
    					}
    					@Override
    					public int compareTo(Pair o) {
    				if(y!=o.y)
    						return o.y-y;
    				else
    					return o.x-x;
    					}
    					public int hashCode() {
    							int hu = (int) (x ^ (x >>> 32));
    							int hv = (int) (y ^ (y >>> 32));
    							//int hw = (int) (mass ^ (mass >>> 32));
    							return 31 * hu + hv ;
    						//return 0;
    						}
    						public boolean equals(Object o) {
    							Pair other = (Pair) o;
    							return x == other.x && y == other.y;
    					//	return false;
    						}
    				}

