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.lang.*;
import java.math.BigInteger;

 
public class Main2{
    public static void main(String args[]) throws IOException
    {
        //Scanner in =new Scanner(new FileReader("input.txt"));
        //PrintWriter out = new PrintWriter(new FileWriter("output.txt"));
        //Scanner in=new Scanner(System.in);
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out=new PrintWriter(System.out);
        StringTokenizer st=new StringTokenizer(br.readLine());
        int n=ni(st.nextToken());
        int k=ni(st.nextToken());
        out.println((6*n-1)*k);
        for(int i=0;i<n;i++)
            out.println(((6*i+1)*k)+" "+((6*i+2)*k)+" "+((6*i+3)*k)+" "+((6*i+5)*k));
        
        
        out.close();
    }
    
        public static Integer ni(String s)
        {
            return Integer.parseInt(s);
        }
        public static BigInteger nb(String s)
        {
            return BigInteger.valueOf(Long.parseLong(s));
        }
        public static Long nl(String s)
        {
            return Long.parseLong(s);
        }
        public static Double nd(String s)
        {
            return Double.parseDouble(s);
        }       
}