Problem: Dreamoon likes to play with sets, integers and <image>. <image> is defined as the largest positive integer that divides both a and b.

Let S be a set of exactly four distinct integers greater than 0. Define S to be of rank k if and only if for all pairs of distinct elements si, sj from S, <image>.

Given k and n, Dreamoon wants to make up n sets of rank k using integers from 1 to m such that no integer is used in two different sets (of course you can leave some integers without use). Calculate the minimum m that makes it possible and print one possible solution.

Input

The single line of the input contains two space separated integers n, k (1 ≤ n ≤ 10 000, 1 ≤ k ≤ 100).

Output

On the first line print a single integer — the minimal possible m. 

On each of the next n lines print four space separated integers representing the i-th set.

Neither the order of the sets nor the order of integers within a set is important. If there are multiple possible solutions with minimal m, print any one of them.

Examples

Input

1 1


Output

5
1 2 3 5


Input

2 2


Output

22
2 4 6 22
14 18 10 16

Note

For the first example it's easy to see that set {1, 2, 3, 4} isn't a valid set of rank 1 since <image>.

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;
import java.util.Arrays;

public class Main {
	
	public static void main(String[] args) {
		
		MyScanner sc = new MyScanner();
		MyWriter mw = new MyWriter();
	
		int n , k  ; 
		
		n = sc.nextInt();
		k = sc.nextInt();
		
		System.out.println( (6*n - 1)*k );
		
		for( int i = 0 ; i < n ; ++i )
		 System.out.println( ( 6*i+ 1 )*k + " "  + ( 6*i+ 2 )*k + " " +  ( 6*i+ 3 )*k + " " + ( 6*i+ 5 )*k ) ; 
		
	}
	
	static class MyScanner {
	      BufferedReader br;
	      StringTokenizer st;
	 
	      public MyScanner() {
	         br = new BufferedReader(new InputStreamReader(System.in),8*1024);
	      }
	 
	      String next() {
	          while (st == null || !st.hasMoreElements()) {
	              try {
	                  st = new StringTokenizer(br.readLine());
	              } catch (IOException e) {
	                  e.printStackTrace();
	              }
	          }
	          return st.nextToken();
	      }
	 
	      int nextInt() {
	          return Integer.parseInt(next());
	      }
	 
	      long nextLong() {
	          return Long.parseLong(next());
	      }
	 
	      double nextDouble() {
	          return Double.parseDouble(next());
	      }
	 
	      String nextLine(){
	          String str = "";
		  try {
		     str = br.readLine();
		  } catch (IOException e) {
		     e.printStackTrace();
		  }
		  return str;
	      }

	   }

	static class MyWriter {
	    BufferedWriter bw;

	    public  MyWriter() {
	       bw = new BufferedWriter(new OutputStreamWriter(System.out),8*1024);
	    }

	    void print(String s)
	    {
	    	try {
					bw.write( s , 0 , s.length() );
					
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
	    }
	    
	    void println(String s)
	    {
	    	try {
				bw.write( s , 0 , s.length() );
				bw.newLine();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
	    }

	 void close()
	 {
		 try {
			bw.close();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	 }
	}
	
	
}