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:
/**
 * Created by Dima on 12.10.2014.
 */

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class TaskD272 {
    private static BufferedReader reader;
    private static PrintWriter writer;
    private static StringTokenizer st;

    public static void main(String[] args) throws IOException {
        reader = new BufferedReader(new InputStreamReader(System.in));
        writer = new PrintWriter(System.out, true);
        solve();
    }

    private static void solve() throws IOException {
        int n = nextInt();
        int k = nextInt();
        int a = 0;
        long m = (n * 6 - 1) * k;
        writer.println(m);
        for(int i = 0; i < n; ++i) {
            for(int j = 0; j < 4; ++j) {
                if(j != 3) a += k;
                else a += 2*k;
                writer.print(a + " ");
            }
            a += k;
            writer.println();
        }
    }

    private static int nextInt() throws IOException {
        return Integer.parseInt(readToken());
    }

    private static String readToken() throws IOException {
        while (st == null || !st.hasMoreElements()) st = new StringTokenizer(reader.readLine(), " ");
        return st.nextToken();
    }
}