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.*;
import java.math.*;
import java.util.regex.*;

public class Task476D {
  public static void main(String[] args) throws IOException {
    BufferedReader f = new BufferedReader(new InputStreamReader(System.in));
    PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
    StringTokenizer st = new StringTokenizer(f.readLine());
    
    int nSetCount = Integer.parseInt(st.nextToken());
    int nGcd = Integer.parseInt(st.nextToken());
    
    out.println((6*nSetCount-1)*nGcd);
    for(int i=0;i<nSetCount;i++)
      out.printf("%d %d %d %d\n",(6*i+1)*nGcd,(6*i+4)*nGcd,
                (6*i+3)*nGcd,(6*i+5)*nGcd);
    
    out.close();
    System.exit(0);
  }
}