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.util.StringTokenizer;


public class B {
    
    void run() {
        FastScanner fs = new FastScanner();
        PrintWriter out = new PrintWriter(System.out);
        int n, k; 
        n = fs.nextInt(); k = fs.nextInt();
        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));
        }
        out.close();
    }
    
    public static void main(String[] args) {
        new B().run();
    }
    
    static class FastScanner{
        BufferedReader br; 
        StringTokenizer st; 
        
        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }
        
        public FastScanner(String s) {
            try {
                br = new BufferedReader(new FileReader(s));
            } catch (FileNotFoundException e) { 
                e.printStackTrace();
            }   
        }
        
        String nextToken() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
        
        String nextLine() {
            try {
                return br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }   
            return null; 
        }
        
        int nextInt() {
            return Integer.parseInt(nextToken());
        }
        
        long nextLong() {
            return Long.parseLong(nextToken());
        }
        
        double nextDouble() {
            return Double.parseDouble(nextToken());
        }
    }
}