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.
/*
 * 
 * @Author  Ajudiya_13(Bhargav Girdharbhai Ajudiya)
 * Dhirubhai Ambani Institute of Information And Communication Technology 
 * 
 */


import java.util.*;
import java.io.*;
import java.lang.*;

public class Code230
{
	
	public static void main(String[] args)
	{
		InputReader in = new InputReader(System.in);
		PrintWriter pw = new PrintWriter(System.out);
	
		long a = in.nextLong();
		long b = in.nextLong();
		
		long p = b-a;
		if(p>=10)
			pw.print("0");
		
		else
		{
			long ans = 1;
			a++;
			for(int i=1;i<=p;i++)
			{
				long c = a%10;
				ans = (ans%10*c%10)%10;
				//System.out.println(ans);
				a++;
			}
			pw.println(ans);
		}
		pw.flush();
		pw.close();
	}
	
	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 int[] nextIntArray(int n) 
		{
			int a[] = new int[n];
			for (int i = 0; i < n; i++) 
			{
				a[i] = nextInt();
			}
			return a;
		}
 
		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);
		}
	}
	
	public static long mod = 1000000007;
	public static int d;
	public static int p;
	public static int q;
	
	public static int[] suffle(int[] a,Random gen)
	{
		int n = a.length;
		for(int i=0;i<n;i++)
		{
			int ind = gen.nextInt(n-i)+i;
			int temp = a[ind];
			a[ind] = a[i];
			a[i] = temp;
		}
		return a;
	}
	
	public static void swap(int a, int b){
		int temp = a;
		a = b;
		b = temp;
	}
	
	public static ArrayList<Integer> primeFactorization(int n)
	{
		ArrayList<Integer> a =new ArrayList<Integer>();
		for(int i=2;i*i<=n;i++)
		{
			while(n%i==0)
			{
				a.add(i);
				n/=i;
			}
		}
		if(n!=1)
			a.add(n);
		return a;
	}
	
	public static void sieve(boolean[] isPrime,int n)
	{
		for(int i=1;i<n;i++)
			isPrime[i] = true;
		
		isPrime[0] = false;
		isPrime[1] = false;
		
		for(int i=2;i*i<n;i++)
		{
			if(isPrime[i] == true)
			{
				for(int j=(2*i);j<n;j+=i)
					isPrime[j] = false;
			}
		}
	}
	
	public static int GCD(int a,int b)
	{
		if(b==0)
			return a;
		else
			return GCD(b,a%b);
	}
	
	public static long GCD(long a,long b)
	{
		if(b==0)
			return a;
		else
			return GCD(b,a%b);
	}
	
	public static void extendedEuclid(int A,int B)
	{
		if(B==0)
		{
			d = A;
			p = 1 ;
			q = 0;
		}
		else
		{
			extendedEuclid(B, A%B);
			int temp = p;
			p = q;
			q = temp - (A/B)*q;
		}
	}
	
	public static long LCM(long a,long b)
	{
		return (a*b)/GCD(a,b);
	}
	
	public static int LCM(int a,int b)
	{
		return (a*b)/GCD(a,b);
	}
	
	public static int binaryExponentiation(int x,int n)
	{
	    int result=1;
	    while(n>0)
	    {
	        if(n % 2 ==1)
	            result=result * x;
	        x=x*x;
	        n=n/2;
	    }
	    return result;
	}
	
	public static long binaryExponentiation(long x,long n)
	{
	    long result=1;
	    while(n>0)
	    {
	        if(n % 2 ==1)
	            result=result * x;
	        x=x*x;
	        n=n/2;
	    }
	    return result;
	}
	
	public static int modularExponentiation(int x,int n,int M)
	{
	    int result=1;
	    while(n>0)
	    {
	        if(n % 2 ==1)
	            result=(result * x)%M;
	        x=(x*x)%M;
	        n=n/2;
	    }
	    return result;
	}
	
	public static long modularExponentiation(long x,long n,long M)
	{
	    long result=1;
	    while(n>0)
	    {
	        if(n % 2 ==1)
	            result=(result * x)%M;
	        x=(x*x)%M;
	        n=n/2;
	    }
	    return result;
	}
	
	public static int modInverse(int A,int M)
	{
	    return modularExponentiation(A,M-2,M);
	}
	
	public static long modInverse(long A,long M)
	{
	    return modularExponentiation(A,M-2,M);
	}
	
	public static boolean isPrime(int n)
	{
	    
	    if (n <= 1)  return false;
	    if (n <= 3)  return true;
	    
	    if (n%2 == 0 || n%3 == 0) 
	    	return false;
	 
	    for (int i=5; i*i<=n; i=i+6)
	    {
	        if (n%i == 0 || n%(i+2) == 0)
	           return false;
	    }
	    
	    return true;
	}
	
	static class pair implements Comparable<pair>
	{
		Integer x, y;
		pair(int x,int y)
		{
			this.x=x;
			this.y=y;
		}
		
		public int compareTo(pair o) {
			int result = x.compareTo(o.x);
			if(result==0)
				result = y.compareTo(o.y);
			
			return result;
		}  
		
		public String toString()
		{
			return x+" "+y;
		}
		
		public boolean equals(Object o)
		{
			if (o instanceof pair)
		    {
				pair p = (pair)o;
				return p.x == x && p.y == y ;
			}
			return false;
		}
		
		public int hashCode()
		{
			return new Long(x).hashCode()*31 + new Long(y).hashCode();
		}
	}
}