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.math.BigInteger;
import java.util.*;
import java.util.concurrent.ArrayBlockingQueue;

import sun.security.provider.certpath.OCSP.RevocationStatus;

public class D
{
	String line;
	StringTokenizer inputParser;
	BufferedReader is;
	FileInputStream fstream;
	DataInputStream in;
	
	void openInput(String file)
	{

		if(file==null)is = new BufferedReader(new InputStreamReader(System.in));//stdin
		else
		{
			try{
		
				
			fstream = new FileInputStream(file);
			in = new DataInputStream(fstream);
			is = new BufferedReader(new InputStreamReader(in));
			}catch(Exception e)
			{
				System.err.println(e);
			}
		}

	}
	
	void readNextLine()
	{
		try {
			line = is.readLine();
			inputParser = new StringTokenizer(line, " ");
			//System.err.println("Input: " + line);
		} catch (IOException e) {
			System.err.println("Unexpected IO ERROR: " + e);
		}	
		
	}
	
	int NextInt()
	{
		String n = inputParser.nextToken();
		int val = Integer.parseInt(n);
		
		//System.out.println("I read this number: " + val);
		return val;
	}
	
	long NextLong()
    {
            String n = inputParser.nextToken();
            
            long val = Long.parseLong(n);
            
            return val;
    }
	
	String NextString()
	{
		String n = inputParser.nextToken();
		return n;
	}
	
	void closeInput()
	{
		try {
			is.close();
		} catch (IOException e) {
			System.err.println("Unexpected IO ERROR: " + e);
		}
			
	}
	
	
	public static void main(String [] argv)
	{
		String filePath=null;
		if(argv.length>0)filePath=argv[0];
		new D(filePath);
	}

	public D(String inputFile)
	{
		openInput(inputFile);
		StringBuilder sb = new StringBuilder();
		readNextLine();
		int n=NextInt();
		int k=NextInt();
		
		TreeSet <Integer> s2 = new TreeSet<Integer>();
		s2.add(1);
		s2.add(2);
		s2.add(3);
		s2.add(5);
		
		for(int y:s2)
			sb.append((y*k)+" ");
		sb.append("\n");
		int x=7;
		int xx=4;
		for(int i=1; i<n; i++)
		{
			s2.clear();
			for(int j=0; j<3; j++)
			{
				s2.add(x);
				x+=2;
			}
			
			boolean good = true;
			do
			{
				good = true;
				for(int y:s2)
					if(GCD(y, xx)>1)
					{
						good = false;
						xx+=2;
						break;
					}
			}while(!good);
			s2.add(xx);
			xx+=2;
			for(int y:s2)
				sb.append((y*k)+" ");
			
			sb.append("\n");
		}
		x-=2;
		sb.insert(0, (x*k)+"\n");
    	System.out.println(sb);
		closeInput();	
	}

	private int GCD(int a, int b)
	{
		return(b==0?a:GCD(b, a%b));
	}
}