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- Priyam Vora
	 * BTech 2nd Year DAIICT
	 */
	     
	     
	        		    import java.awt.Checkbox;
	import java.awt.Point;
	import java.awt.event.PaintEvent;
	import java.io.*;
	        		    import java.math.*;
	        		    import java.util.*;
	import java.util.Map.Entry;
	
	import javax.print.attribute.SetOfIntegerSyntax;
	import javax.swing.plaf.FontUIResource;
	    	     
	        		    public class Main{
	        		  	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 count = 0,mod=1000000007;
	        		    //	private static TreeSet<Integer> ts=new TreeSet[200000];
	public final static int INF = (int) 1E9;
	
	public static void main(String args[]) {
		InputReader(System.in);
		pw = new PrintWriter(System.out); 
	    new Thread(null ,new Runnable(){
	       public void run(){
	           try{
	               solve();
	               
	               pw.close();
	           } catch(Exception e){
	               e.printStackTrace();
	           }
	       }
	   },"1",1<<26).start();
	   }
	    static StringBuilder sb;
	    public static void test(){
	    	 sb=new StringBuilder();
	    	int t=nextInt();
	    	while(t-->0){
	    		
	    		solve();
	    		//pw.println();
	    		//sb.append("\n");
	    	}
	    	pw.println(sb);
	    }
	    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 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 void Merge(long a[],int p,int r){
	        if(p<r){
	            int q = (p+r)/2;
	            Merge(a,p,q);
	            Merge(a,q+1,r);
	            Merge_Array(a,p,q,r);
	        }
	    }
	    public static void Merge_Array(long a[],int p,int q,int r){
	       long b[] = new long[q-p+1];
	        long c[] = new long[r-q];
	        for(int i=0;i<b.length;i++)
	            b[i] = a[p+i];
	        for(int i=0;i<c.length;i++)
	            c[i] = a[q+i+1];
	        int i = 0,j = 0;
	        for(int k=p;k<=r;k++){
	            if(i==b.length){
	                a[k] = c[j];
	                j++;
	            }
	            else if(j==c.length){
	                a[k] = b[i];
	                i++;
	            }
	            else if(b[i]<c[j]){
	                a[k] = b[i];
	                i++;
	            }
	            else{
	                a[k] = c[j];
	                j++;
	            }
	        }
	    }
	    
	  
		public static long gcd(long x, long y) {
			if (x == 0)
				return y;
			else
				return gcd( y % x,x);
		}	
		
		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 LinkedList<Integer> adj[];
	        static boolean Visited[];
	        static HashSet<Integer> exc;
	        static long oddsum[]=new long[1000001];
	        static long co=0,ans=0;
	    
	    	private static void buildgraph(int n){
	    		adj=new LinkedList[n+1];
	    		Visited=new boolean[n+1];
	    		levl=new int[n+1];
	    		
	    		for(int i=0;i<=n;i++){
	    			adj[i]=new LinkedList<Integer>();
	    		
	    		}
	
	
	    	}
	      
	       
	        static int[] levl;
	        static int[] eat;
	        static int n,m;
	        static int price[];
	        //ind frog crab
	    
	        
	        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 double distance(int x1,int y1,int x2,int y2){
	        	return Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));
	        }
	        static double area(int x1, int y1, int x2, int y2, int x3, int y3)
	        {
	           return Math.abs((x1*(y2-y3) + x2*(y3-y1)+ x3*(y1-y2))/2.0);
	        }
	        static boolean isInside(int x1, int y1, int x2, int y2, int x3, int y3, int x, int y)
	        {   
	           double A = area (x1, y1, x2, y2, x3, y3);
	         
	           double A1 = area (x, y, x2, y2, x3, y3);
	         
	           double A2 = area (x1, y1, x, y, x3, y3);
	         
	           double A3 = area (x1, y1, x2, y2, x, y);
	           
	          return (A == A1 + A2 + A3);
	        }
	      
			static int col[];
	    public static boolean isVowel(char c){
	    	if(c=='a' || c=='e'||c=='i' || c=='o' || c=='u')
	    		return true;
	    	return false;
	    }
	static Stack<Integer> st[];
	static Queue<Integer> q[];
	static long cost[];    
	public static void solve(){

		long a=nextLong();
		long b=nextLong();
		if(a==0){
			if(b>=5){
				pw.println(0);
			}else{
				
				if(b==1 || b==0){
					pw.println(1);
				}
				if(b==2){
					pw.println(2);
				}
				if(b==3){
					pw.println(6);
				}
				if(b==4){
					pw.println(4);
				}
			}
		}else{
            if (b < 10) {
                pw.println((factorial(b) / factorial(a)) % 10);
            } else if (b - a >= 10) pw.println(0);
            else {
                BigInteger temp = BigInteger.ONE;
                for (long i = b; i > a; i--) temp = temp.multiply(BigInteger.valueOf(i));
                pw.println(temp.mod(BigInteger.valueOf(10)));
            }
        }

	}
    public static long factorial(long n) {
        long a = 1;
        for (long i = 1; i <= n; i++) a *= i;
        return a;
    }

 
	static int numberOfPaths(int m, int n)
    {
        // Create a 2D table to store results 
        // of subproblems
        int count[][] = new int[m][n];
  
        // Count of paths to reach any cell in 
        // first column is 1
        for (int i = 0; i < m; i++)
            count[i][0] = 1;
  
        // Count of paths to reach any cell in
        // first column is 1
        for (int j = 0; j < n; j++)
            count[0][j] = 1;
  
        // Calculate count of paths for other 
        // cells in bottom-up manner using
        // the recursive solution
        for (int i = 1; i < m; i++)
        {
            for (int j = 1; j < n; j++)
  
            // By uncommenting the last part the 
            // code calculatest he total possible paths 
            // if the diagonal Movements are allowed
            count[i][j] = count[i-1][j] + count[i][j-1]; //+ count[i-1][j-1];
  
        }
        return count[m-1][n-1];
    }
	static int no_vert=0;
	private static void dfs2(int s){
		Visited[s]=true;
		no_vert++;
		sb.append(s+" ");
		for(int x:pri[s]){
			if(!Visited[x]){
			
				dfs2(x);
			}
			
		}
	}
	
	private static void dfs4(int s){
		Visited[s]=true;
		no_vert++;
		sb.append(s+" ");
		for(int x:pri2[s]){
			if(!Visited[x]){
			
				dfs4(x);
			}
			
		}
	}
	
	    private static boolean Check(int x,int y,int n){
			if(x>=0 && x<n && y>=0 && y<n)
				return true;
			return false;
		}
	    
	    static long dp[],dp2[];
	    static ArrayList<Integer> pri[],pri2[];
	  private static void dfs(int curr,int par,int co){
		 Visited[curr]=true;
		 for(int x:adj[curr]){
			 if(!Visited[x]){
				 dfs(x,curr,co);
			 }
		 }
		 if(col[curr]==0){
			 dp[curr]++;
		 }else{
			 dp[curr]--;
		 }
		 if(dp[curr]>0){
			 pri[par].add(curr);
		 dp[par]+=dp[curr];
		 }
	  }
	  private static void dfs3(int curr,int par,int co){
			 Visited[curr]=true;
			 for(int x:adj[curr]){
				 if(!Visited[x]){
					 dfs3(x,curr,co);
				 }
			 }
			 if(col[curr]==1){
				 dp2[curr]++;
			 }else{
				 dp2[curr]--;
			 }
			 if(dp2[curr]>0){
				 pri2[par].add(curr);
			 dp2[par]+=dp2[curr];
			 }
		  }
	    public static String reverseString(String s) {
			StringBuilder sb = new StringBuilder(s);
			sb.reverse();
			return (sb.toString());
		}
	    
	  /*  
	   private static void BFS(int sou){
	    	Queue<Integer> q=new LinkedList<Integer>();
	    	q.add(sou);
	    	Visited[sou]=true;
	    	levl[sou]=0;
	    	while(!q.isEmpty()){
	    		int top=q.poll();
	    		
	    		for(int i:adj[top]){
	    			//pw.println(i+" "+top);
				if(!Visited[i])
				{
					
					q.add(i);
					levl[i]=levl[top]+1;
				}
				
				Visited[i]=true;
				
				}
			}
		}*/
		
	
	
	
	    		      static int indeg[];
	    		   /* private static void kahn(int n){
	    		    	
	    		    	PriorityQueue<Integer> q=new PriorityQueue<Integer>();
	    				for(int i=1;i<=n;i++){
	    					if(indeg[i]==0){
	    						q.add(i);
	    					}
	    				}
	    				while(!q.isEmpty()){
	    					int top=q.poll();
	    					st.push(top);
	    					for(Node i:adj[top]){
	    						indeg[i.to]--;
	    						if(indeg[i.to]==0){
	    							q.add(i.to);
	    						}
	    					}
	    				}
	    		    }
	    		        
	    		        static int state=1;
	    		        static long no_exc=0,no_vert=0;
	    		      static Stack<Integer> st;
	    		      static HashSet<Integer> inset;
	    		     /*   private static void topo(int curr){
	    		        	
	    		        	Visited[curr]=true;
	    		        	inset.add(curr);
	    		        	for(int x:adj[curr]){
	    		        		if(adj[x].contains(curr) || inset.contains(x)){
	    		        			state=0;
	    		        			return;
	    		        		}
	    		        		if(state==0)
	    		        			return;
	    		        		
	    		        	}
	    		        	st.push(curr);
	    		        	
	    		        	inset.remove(curr);
	    		        }*/
	    		        static HashSet<Integer> hs;
	    		       
	    		     
	    		     	static boolean prime[];
						static int spf[];
						public static void sieve(int n){
							prime=new boolean[n+1];
							spf=new int[n+1];
							
							Arrays.fill(spf, 1);
							Arrays.fill(prime, true);
						prime[1]=false;
							spf[2]=2;
							
						for(int i=4;i<=n;i+=2){
							spf[i]=2;
						}
						for(int i=3;i<=n;i+=2){
							if(prime[i]){
								spf[i]=i;
								for(int j=2*i;j<=n;j+=i){
									
									prime[j]=false;
								if(spf[j]==1){
									spf[j]=i;
								}
								}
							}
						}
						
							
						}
	    		     	
	    		    	// To Get Input
	// Some Buffer Methods
	 
	    		     	public static void sort(long a[]){
	    		     		Merge(a, 0, a.length-1);
	    		     	}
	    		    	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 long[][] next2dArray(int n, int m) {
	    		    		long[][] arr = new long[n][m];
	    		    		for (int i = 0; i < n; i++) {
	    		    			for (int j = 0; j < m; j++) {
	    		    				arr[i][j] = nextLong();
	    		    			}
	    		    		}
	    		    		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().split(" ");
	    		    			for(int j=0;j<s.length;j++){
	    		    				c[i][j]=s[j].charAt(0);
	    		    			}
	    		    		}
	    		    		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 Node{
	    		    	int to;
	    		    	long dist;
	    		    	Node(int to,long dist){
	    		    		this.to=to;
	    		    		this.dist=dist;
	    		    	}
	    		    	
	    		    }
	    		
	class Dsu{
	private int rank[], parent[] ,n;
	long str[],si[],larg[];
	long max=0;
	int cnt=0;
	private static int[] parent1;
	Dsu(int size){
		this.n=size+1;
		rank=new int[n];
		cnt=n-1;
		//parent=new int[n];
	    		    		    		parent=new int[n];
	    		    		    		str=new long[n];
	    		    		    		si=new long[n];
	    		    		
	    		    		    		larg=new long[n];
	    		    		    		makeSet();
	    		    		
	    		    		    	}
	    		    		    	
	    		    		    	void makeSet(){
	    		    		    		for(int i=0;i<n;i++){
	    		    		    			parent[i]=i;
	    		    		    			si[i]=1;
	    		    		    		}
	    		    		    	}
	    		    		    	
	    		    		    	int find(int x){
	    		    		    		if(parent[x]!=x){
	    		    		    			
	    		    		    			parent[x]=find(parent[x]);
	    		    		    		}
	    		    		    		return parent[x];
	    		    		    	}
	    		    		    	
	    		    		    	void join(int ind,long val){
	    		    		    		if(str[ind]==0){
	    		    		    			str[ind]=val;
	    		    		    			larg[ind]=val;
	    		    		    			max=Math.max(max, str[ind]);
	    		    		    		}
	    		    		    		int prev_ind=(ind-1);
	    		    		    		int next_ind=(ind+1);
	    		    		    		if(prev_ind>0 && larg[prev_ind]!=0){
	    		    		    			union(prev_ind,ind);
	    		    		    		}
	    		    		    		if(next_ind<n && larg[next_ind]!=0){
	    		    		    			union(next_ind,ind);
	    		    		    		}
	    		    		    		
	    		    		    	}
	    		    		    
	    		    		    	
	    		    		    	boolean union(int x,int y){
	    		    		    		int xRoot=find(x);
	    		    		    		int yRoot=find(y);
	    		    		    
	    		    		    	
	    		    		    		if(xRoot==yRoot)
	    		    		    			return false;
	    		    		    		if(rank[xRoot]<rank[yRoot]){
	    		    		    		parent[xRoot]=yRoot;
	    		    		    		
	    		    		    		larg[yRoot]=Math.max(larg[xRoot], larg[yRoot]);
	    		    		    		
	    		    		    		si[yRoot]+=si[xRoot];
	    		    		    		str[yRoot]=larg[yRoot]*si[yRoot];
	    		    		    			max=Math.max(str[yRoot], max);
	    		    		    		}else if(rank[yRoot]<rank[xRoot]){
	    		    		    			parent[yRoot]=xRoot;
	     
	    		    		    			larg[xRoot]=Math.max(larg[xRoot], larg[yRoot]);
	        		    		    		
	        		    		    		si[xRoot]+=si[yRoot];
	        		    		    		str[xRoot]=larg[xRoot]*si[xRoot];
	    			    		    		max=Math.max(str[xRoot], max);
	    		    		    		}else{
	    		    		    			parent[yRoot]=xRoot;
	    		    		    			rank[xRoot]++;
	     
	    		    		    			larg[xRoot]=Math.max(larg[xRoot], larg[yRoot]);
	        		    		    		
	        		    		    		si[xRoot]+=si[yRoot];
	        		    		    		str[xRoot]=larg[xRoot]*si[xRoot];
	    			    		    		max=Math.max(str[xRoot], max);
	    		    		    		
	    		    		    		}
	    		    		    		cnt--;
	    		    		    		return true;
	    		    		    	}
	    	
	    		    		     
	    		    		    }
	class Pair implements Comparable<Pair>{
		int x,y,w;
		Pair(int x,int y){
			this.x=x;
			this.y=y;
		}
	
		@Override
		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			return 0;
		}
	}
	  
								
