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.StringTokenizer;

/**
 * Codeforces 476D - Dreamoon and Sets
 * Created by Darren on 14-10-18.
 */
public class D {
    Reader in = new Reader(System.in);
    PrintWriter out = new PrintWriter(System.out);

    public static void main(String[] args) throws IOException {
        new D().run();
    }

    void run() throws IOException {
        int n = in.nextInt(), k = in.nextInt();

        out.println(((n-1) * 6 + 5) * k);
        for (int i = 0; i < n; i++) {
            out.print((i * 6 + 1) * k);
            out.print(' ');
            out.print((i * 6 + 2) * k);
            out.print(' ');
            out.print((i * 6 + 3) * k);
            out.print(' ');
            out.println((i * 6 + 5) * k);
        }
        out.flush();
    }

    static class Reader {
        BufferedReader reader;
        StringTokenizer tokenizer;

        public Reader(InputStream input) {
            reader = new BufferedReader(new InputStreamReader(input));
            tokenizer = new StringTokenizer("");
        }

        /** get next word */
        String nextToken() throws IOException {
            while ( ! tokenizer.hasMoreTokens() ) {
                //TODO add check for eof if necessary
                tokenizer = new StringTokenizer( reader.readLine() );
            }
            return tokenizer.nextToken();
        }

        String readLine() throws IOException {
            return reader.readLine();
        }

        int nextInt() throws IOException {
            return Integer.parseInt( nextToken() );
        }

        long nextLong() throws IOException {
            return Long.parseLong( nextToken() );
        }

        double nextDouble() throws IOException {
            return Double.parseDouble( nextToken() );
        }
    }
}