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.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Collections;
import java.util.HashSet;
import java.util.Map;
import java.util.Random;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.TreeSet;

public class solver {
    
    BufferedReader in;
    PrintWriter out;
    StringTokenizer tok;
    
    static final boolean OJ = System.getProperty("ONLINE_JUDGE") != null;
    
    void init() throws FileNotFoundException{
        if (OJ){
          in = new BufferedReader(new InputStreamReader(System.in));
          out = new PrintWriter(System.out);
//          in = new BufferedReader(new FileReader("sandwiches.in"));
//          out = new PrintWriter("sandwiches.out");
        }else{
            in = new BufferedReader(new FileReader("input.txt"));
            out = new PrintWriter("output.txt");
        }
    }
    
    String readString() throws IOException{
        while (tok == null || !tok.hasMoreTokens()){
            tok = new StringTokenizer(in.readLine()," :");
        }
        return tok.nextToken();
    }
    
    int readInt() throws NumberFormatException, IOException{
        return Integer.parseInt(readString());
    }
    
    double readDouble() throws NumberFormatException, IOException{
        return Double.parseDouble(readString());
    }
    
    long readLong() throws NumberFormatException, IOException{
        return Long.parseLong(readString());
    }
    long time;
    void run(){
        try{
            time = System.currentTimeMillis();
            init();
            solve();
            System.err.println(System.currentTimeMillis() - time);
            out.close();
            in.close();
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    
    long gcd(long a, long b){
        if (a == 0) return b;
        return gcd(b % a, a);
    }
    
    int getNumberSum(long x){
        long sum = 0;
        while (x > 0){
            sum += x % 10;
            x /= 10;
        }
        return (int)sum;
    }
    
            
    void solve() throws NumberFormatException, IOException{
        int n = readInt();
        int k = readInt();
        out.println(k*(6*(n-1)+5));
        for (int i=0;i<n;i++){
            out.println(k*(6*i+1)+" "+k*(6*i+2)+" "+k*(6*i+3)+" "+k*(6*i+5));
        }
    }

    public static void main(String[] args) {
        new solver().run();
    }

}