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.*;
public class CF_476D {
    public static void main(String[] args) throws IOException {
        new CF_476D().solve();
    }
    
    
    void solve() throws IOException{
        
        InputStream in = System.in;
        PrintStream out = System.out;
        
//        in = new FileInputStream("in.txt");
//        out = new PrintStream("out.txt");
        
        Scanner sc=new Scanner(in);
        int n=sc.nextInt(), k=sc.nextInt();
        
        int max=0;
        StringBuilder ans=new StringBuilder();
        for (int i=0;i<n;i++){
            ans.append(k*(6*i+1)+" "+k*(6*i+2)+" "+k*(6*i+3)+" "+k*(6*i+5)+"\n");
            max=k*(6*i+5);
        }
        out.println(max);
        out.println(ans.toString());
            
        
    }
}