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.util.*;
import java.lang.String;
import java.lang.Math;
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;
import javax.swing.JOptionPane;

public class Solution {
	
public static long mod = 1000000007;
	
	
	public static void main(String args[])throws IOException
	{
		long n = nextLong();
		long k = nextLong();
		long mx = k*(6*n-1);
		System.out.println(mx);
		for(long i = 0;i<n;i++)
		{
			long a = 6*i + 1;
			long b = 6*i + 2;
			long c = 6*i + 3;
			long d = 6*i + 5;
			System.out.println(a*k + " " + b*k + " " + c*k + " " + d*k);
		}
	}
	
	
    static BufferedReader reader = new BufferedReader(new InputStreamReader(
            System.in));
    static StringTokenizer tokenizer = new StringTokenizer("");

    static String next() throws IOException {
        while (!tokenizer.hasMoreTokens()) {
            String n = reader.readLine();
            if (n == null) {
                return null;
            }
            tokenizer = new StringTokenizer(n);

        }
        return tokenizer.nextToken();
    }

    static String nextLine() throws IOException {
        return reader.readLine();
    }

    static Integer nextInt() throws IOException {
        String next = next();
        if (next == null) {
            return null;
        }
        return Integer.parseInt(next);
    }

    static long nextLong() throws IOException {
        return Long.parseLong(next());
    }

    static Double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }
    
    

}