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.*;
import java.io.*;

public class DreamoonAndSets {
    public static InputReader in;
    public static PrintWriter out;

    public static final int MOD = (int) (1e9 + 7);

    public static void main(String[] args) {
	in = new InputReader(System.in);
	out = new PrintWriter(System.out);
	
	int n = in.nextInt(), k = in.nextInt();
	
	out.println((6*n - 1)*k);
	for (int i = 0; i < n; i++) {
	    int[] x = new int[] {6*i + 1, 6*i + 2, 6*i + 3, 6*i + 5};
	    for (int j : x) {
		out.print(k*j + " ");
	    }
	    out.println();
	}

	out.close();
    }

    static class Node implements Comparable<Node> {
	int next;
	int dist;

	public Node(int u, int v) {
	    this.next = u;
	    this.dist = v;
	}

	public void print() {
	    out.println(next + " " + dist + " ");
	}

	public int compareTo(Node that) {
	    return Integer.compare(this.next, that.next);
	}
    }

    static class InputReader {

	private InputStream stream;
	private byte[] buf = new byte[8192];
	private int curChar, snumChars;
	private SpaceCharFilter filter;

	public InputReader(InputStream stream) {
	    this.stream = stream;
	}

	public int snext() {
	    if (snumChars == -1)
		throw new InputMismatchException();
	    if (curChar >= snumChars) {
		curChar = 0;
		try {
		    snumChars = stream.read(buf);
		} catch (IOException e) {
		    throw new InputMismatchException();
		}
		if (snumChars <= 0)
		    return -1;
	    }
	    return buf[curChar++];
	}

	public int nextInt() {
	    int c = snext();
	    while (isSpaceChar(c))
		c = snext();
	    int sgn = 1;
	    if (c == '-') {
		sgn = -1;
		c = snext();
	    }
	    int res = 0;
	    do {
		if (c < '0' || c > '9')
		    throw new InputMismatchException();
		res *= 10;
		res += c - '0';
		c = snext();
	    } while (!isSpaceChar(c));
	    return res * sgn;
	}

	public long nextLong() {
	    int c = snext();
	    while (isSpaceChar(c))
		c = snext();
	    int sgn = 1;
	    if (c == '-') {
		sgn = -1;
		c = snext();
	    }
	    long res = 0;
	    do {
		if (c < '0' || c > '9')
		    throw new InputMismatchException();
		res *= 10;
		res += c - '0';
		c = snext();
	    } while (!isSpaceChar(c));
	    return res * sgn;
	}

	public int[] nextIntArray(int n) {
	    int a[] = new int[n];
	    for (int i = 0; i < n; i++)
		a[i] = nextInt();
	    return a;
	}

	public String readString() {
	    int c = snext();
	    while (isSpaceChar(c))
		c = snext();
	    StringBuilder res = new StringBuilder();
	    do {
		res.appendCodePoint(c);
		c = snext();
	    } while (!isSpaceChar(c));
	    return res.toString();
	}

	public boolean isSpaceChar(int c) {
	    if (filter != null)
		return filter.isSpaceChar(c);
	    return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	}

	public interface SpaceCharFilter {
	    public boolean isSpaceChar(int ch);
	}
    }
}