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.util.Scanner;

public class Main {

	public static void main(String[] args) {
		solve();
	}

	private static void solve() {
		int n = IO.readInt();
		int k = IO.readInt();
		
		int m = k * (n * 6 - 1);
		IO.println(m);
		
		for (int i = 0; i < n; ++i) {
			IO.println(k * (6 * i + 1) + " " + k * (6 * i + 2) + " " + k * (6 * i + 3) + " " + k * (6 * i + 5));
		}
	}

	private static class IO {
		static {
			setUpScanner();
		}

		private static Scanner scanner;

		private static void setUpScanner() {
			scanner = new Scanner(new java.io.BufferedInputStream(System.in));
		};

		public static boolean isEmpty() {
			return !scanner.hasNext();
		}

		public static boolean hasNextLine() {
			return scanner.hasNextLine();
		}

		public static String readLine() {
			String line;
			try {
				line = scanner.nextLine();
			} catch (Exception e) {
				line = null;
			}
			return line;
		}

		public static String readString() {
			return scanner.next();
		}

		public static int readInt() {
			return scanner.nextInt();
		}

		public static double readDouble() {
			return scanner.nextDouble();
		}

		public static float readFloat() {
			return scanner.nextFloat();
		}

		public static long readLong() {
			return scanner.nextLong();
		}

		public static void print(Object o) {
			System.out.print(o.toString());
		}

		public static void println(Object o) {
			System.out.println(o);
		}
	}

}