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.InputStreamReader;
import java.io.FileReader;
import java.io.BufferedReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.StringTokenizer;
import java.io.InputStream;

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

class TaskB {
	OutputWriter out;
	InputReader in;
	public void solve(int testNumber, InputReader in, OutputWriter out) {
		this.in = in; this.out = out;
		int n = in.readInt();
		int k = in.readInt();
		int[] nums = {1, 2, 3, 5};
		StringBuilder ans = new StringBuilder();
		int m = 1;
		for (int i = 1; i <= n; i++) {
			for (int j = 0; j < 4; j++) {
				ans.append(nums[j] * k);
				ans.append(" ");
				m = Math.max(m, nums[j] * k);
				nums[j] += 6;
			}
			ans.append(System.lineSeparator());
		}
		out.println(m);
		out.print(ans);
	}
}

class OutputWriter {
	private PrintWriter output;
	public OutputWriter(OutputStream out) {
		output = new PrintWriter(out);
	}
	public void print(Object o) {
		output.print(o);
	}
	public void println(Object o) {
		output.println(o);
	}
	public void close() {
		output.close();
	}
}

class InputReader {
	private BufferedReader input;
	private StringTokenizer line = new StringTokenizer("");
	public InputReader(InputStream in) {
		input = new BufferedReader(new InputStreamReader(in));
	}
	public void fill() {
		try {
			if(!line.hasMoreTokens()) line = new StringTokenizer(input.readLine());
		} catch(IOException io) { io.printStackTrace(); System.exit(0);}
	}
	public int readInt() {
		fill();
		return Integer.parseInt(line.nextToken());
	}
}