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.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Stack;

//: God does not play dice with the world :)
 public class Main{
     
     static List<Integer> sieve(int n) {
         List<Integer> A = new ArrayList<>();
         boolean[] primes = new boolean[n+1];
         Arrays.fill(primes, true);
         for(int i=2;i<=Math.sqrt(n);i++) {
             if(primes[i]) {
                 
                 for(int j=i*i;j<=n;j+=i) {
                     primes[j]=false;
                 }
             }
         }
         for(int i=2;i<=n;i++) {
             if(primes[i]) A.add(i);
         }
         return A;
     }

     public static void main(String[] args) throws IOException {
//        String IN = "C:\\Users\\ugochukwu.okeke\\Desktop\\in.file";
//        String OUT = "C:\\Users\\ugochukwu.okeke\\Desktop\\out.file";
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        //System.out.println((-50+50*15)%15);
        
        String[] in=br.readLine().split(" ");
        int n = Integer.parseInt(in[0]);
        int k = Integer.parseInt(in[1]);
        bw.append((6*n-1)*k+"\n");
        for(int i=0;i<n;i++) {
            bw.append((6*i+1)*k+" "+(6*i+2)*k+" "+(6*i+3)*k+" "+(6*i+5)*k+"\n");
        }
        
        bw.close();
     }

    
 }