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.IOException;
import java.io.PrintWriter;
import java.util.Scanner;

public class B {

    static void solve() throws IOException {
        int n = in.nextInt();
        int k = in.nextInt();
        int max = k * (6 * n - 1);
        out.println( max );
        for ( int i = 0; i < n; i ++ ) {
            for ( int j = 1; j <= 5; j ++ ) {
                if ( j == 4 ) {
                    continue;
                }
                out.print( k * ( i * 6 + j ) + " " );
            }
            out.println();
        }
    }

    static Scanner in;
//    static StreamTokenizer in;
    static PrintWriter out;

//    static int nextInt() throws IOException {
//        in.nextToken();
//        return ( int ) in.nval;
//    }

    public static void main( String[] args ) throws IOException {
        in = new Scanner( System.in );
//        in = new StreamTokenizer( new InputStreamReader( System.in ) );
        out = new PrintWriter( System.out );
        solve();
        out.close();
    }
}