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

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author mthai
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        CF_476D solver = new CF_476D();
        solver.solve(1, in, out);
        out.close();
    }

    static class CF_476D {
        public void solve(int testNumber, Scanner input, PrintWriter out) {
            ShortScanner in = new ShortScanner(input);
            int n = in.i(), k = in.i();
            int m = (6 * n - 1) * k;
            out.println(m);
            for (int i = 0; i <= n - 1; ++i) {
                out.printf("%d %d %d %d\n", k * (6 * i + 1),
                        k * (6 * i + 2), k * (6 * i + 3), k * (6 * i + 5));
            }
        }

        class ShortScanner {
            Scanner in;

            ShortScanner(Scanner in) {
                this.in = in;
            }

            int i() {
                return in.nextInt();
            }

        }

    }
}