Even if the world is full of counterfeits, I still regard it as wonderful.

Pile up herbs and incense, and arise again from the flames and ashes of its predecessor — as is known to many, the phoenix does it like this.

The phoenix has a rather long lifespan, and reincarnates itself once every a! years. Here a! denotes the factorial of integer a, that is, a! = 1 × 2 × ... × a. Specifically, 0! = 1.

Koyomi doesn't care much about this, but before he gets into another mess with oddities, he is interested in the number of times the phoenix will reincarnate in a timespan of b! years, that is, <image>. Note that when b ≥ a this value is always integer.

As the answer can be quite large, it would be enough for Koyomi just to know the last digit of the answer in decimal representation. And you're here to provide Koyomi with this knowledge.

Input

The first and only line of input contains two space-separated integers a and b (0 ≤ a ≤ b ≤ 1018).

Output

Output one line containing a single decimal digit — the last digit of the value that interests Koyomi.

Examples

Input

2 4


Output

2


Input

0 10


Output

0


Input

107 109


Output

2

Note

In the first example, the last digit of <image> is 2;

In the second example, the last digit of <image> is 0;

In the third example, the last digit of <image> is 2.
import java.util.*;
import java.io.*;
public class Main
{
 
	static ArrayList<Integer> adj[];
	static char color[];
	static boolean b[],visited[],possible;
	static int level[];
	static Map<Integer,HashSet<Integer>> s;
	static int totalnodes,colored;
	static int count[];
	static long sum[];
	static int nodes;
	static double ans=0;
	static long[] as=new long[10001];
	static long c1=0,c2=0;
	static int[] a,d,k;
	static int max=100000000;
	static long MOD = (long)1e9 + 7;
	static boolean[] prime=new boolean[100005];
	public static void main(String[] args) throws IOException
	{
		in=new InputReader(System.in);
		w=new PrintWriter(System.out);
	 long a=in.nextLong();
	 long b=in.nextLong();
	 long ans=1;
	 if(b-a>10)
		 w.print(0);
	 else
	 {
	 for(long i=b;i>a;i--)
	 {
		 long t=i%10;
		 ans=ans*t;
		 ans=ans%10;
	 }
	w.print(ans);
	 }
	 w.close();
    }
	public static void sieveOfEratosthenes()
	    {
	       int n=prime.length;
	        for(int i=0;i<n;i++)
	            prime[i] = true;
	         
	        for(int p = 2; p*p <=n; p++)
	        {
	            if(prime[p] == true)
	            {
	                for(int i = p*2; i <= n; i += p)
	                    prime[i] = false;
	            }
	        }
	    }
	public static int[] kthAncestors(int[] a,int[] c,int n,int k)
	{
		int[] ans=new int[n+1];
		ans[1]=-1;
		for(int i=2;i<=n;i++)
		{
			int temp=0;
			boolean r=false;
			int j=i;
			while(a[j]!=j)
			{
				if(c[j]==c[a[j]])
					temp++;
				if(temp==k)
					{
					ans[i]=a[j];
					r=true;
					break;
					}
				j=a[j];
			}
			if(r==false)
				ans[i]=-1;
		}
		
		return ans;
	}
	public static void printDivisors(int n)
    {
        for (int i=1; i<=Math.sqrt(n); i++)
        {
            if (n%i==0)
            {
                if (n/i == i)
                    k[i]++;
                else 
                {
                	k[i]++;
                	k[n/i]++;
                }
            }
        }
    }
   private static void nextIntArray() 
	{
	   int n=a.length;
		 for(int i=0;i<n;i++)
			 a[i]=in.nextInt();
		
	}
	
  public static void bfs()
  {
	 level[1]=1;
	 visited[1]=true;
	 Queue<Integer> q=new LinkedList<Integer>();
	 q.add(1);
	 while(!q.isEmpty())
	 {
		 int t=q.poll();
		 for(int i=0;i<adj[t].size();i++)
		 {
			 if(!visited[adj[t].get(i)])
			 {
				 level[adj[t].get(i)]=level[t]+1;
				 visited[adj[t].get(i)]=true;
				 q.add(adj[t].get(i));
			 }
		 }
	 }
  }
  
  public static void dfs(int i)
  {
	  visited[i]=true;
	  for(int j:adj[i])
	  {
		  if(!visited[j])
			  {
			  dfs(j);
			  nodes++;
			  }
	  }
	  
  }
  public static String rev(String s)
	{
		StringBuilder sb=new StringBuilder(s);
		sb.reverse();
		return sb.toString();
	}
	static long lcm(long a, long b)
	{
	    return a * (b / gcd(a, b));
	}
	static long gcd(long a, long b)
	{
	    while (b > 0)
	    {
	        long temp = b;
	        b = a % b; // % is remainder
	        a = temp;
	    }
	    return a;
	}
	static InputReader in;
	static PrintWriter w;
static class InputReader 
{
 
private final InputStream stream;
private final byte[] buf = new byte[8192];
private int curChar, snumChars;
private SpaceCharFilter filter;
 
public InputReader(InputStream stream)
{
  this.stream = stream;
}
 
public int snext()
{
  if (snumChars == -1)
    throw new InputMismatchException();
  if (curChar >= snumChars)
  {
    curChar = 0;
    try 
    {
      snumChars = stream.read(buf);
    }
    catch (IOException e)
    {
      throw new InputMismatchException();
    }
    if (snumChars <= 0)
      return -1;
  }
  return buf[curChar++];
}
 
public int nextInt() 
{
  int c = snext();
  while (isSpaceChar(c)) 
  {
    c = snext();
  }
  int sgn = 1;
  if (c == '-')
  {
    sgn = -1;
    c = snext();
  }
  int res = 0;
  do
  {
    if (c < '0' || c > '9')
      throw new InputMismatchException();
    res *= 10;
    res += c - '0';
    c = snext();
  }
  while (!isSpaceChar(c));
  return res * sgn;
}
 
public long nextLong() 
{
  int c = snext();
  while (isSpaceChar(c)) 
  {
    c = snext();
  }
  int sgn = 1;
  if (c == '-')
  {
    sgn = -1;
    c = snext();
  }
  long res = 0;
  do
  {
    if (c < '0' || c > '9')
      throw new InputMismatchException();
    res *= 10;
    res += c - '0';
    c = snext();
  }
  while (!isSpaceChar(c));
  return res * sgn;
}
 
public static void nextIntArray(int n) 
{
	 for(int i=0;i<n;i++)
		 a[i]=in.nextInt();
}
	    
public int[] nextIntArray(int n, int off)
{
	 int[] arr = new int[n + off];
	   for (int i = 0; i < n; i++)
	   {
	    arr[i + off] = nextInt();
	    }
	    return arr;
	    }
	    
public long[] nextLongArray(int n)
{
return nextLongArray(n, 0);
	    }
        
	public long[] nextLongArray(int n, int off)
	{
	 long[] arr = new long[n + off];
	 for (int i = 0; i < n; i++)
	 {
		  arr[i + off] = nextLong();
		 }
 return arr;
	}
 
 
public String readString() 
{
  int c = snext();
  while (isSpaceChar(c)) 
  {
    c = snext();
  }
  StringBuilder res = new StringBuilder();
  do
  {
    res.appendCodePoint(c);
    c = snext();
  }
  while (!isSpaceChar(c));
  return res.toString();
}
 
public String nextLine() 
{
  int c = snext();
  while (isSpaceChar(c))
    c = snext();
  StringBuilder res = new StringBuilder();
  do
  {
    res.appendCodePoint(c);
    c = snext();
  }
  while (!isEndOfLine(c));
  return res.toString();
}
 
public boolean isSpaceChar(int c)
{
  if (filter != null)
    return filter.isSpaceChar(c);
  return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
}
 
private boolean isEndOfLine(int c) 
{
  return c == '\n' || c == '\r' || c == -1;
}
 
public interface SpaceCharFilter
{
  public boolean isSpaceChar(int ch);
}
}
	
}