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.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;


public class DreamoonAndSets {

	public static void main(String args[] ) throws Exception {
		
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	    PrintWriter w = new PrintWriter(System.out);
	        
	    StringTokenizer st1 = new StringTokenizer(br.readLine());
	    int n = ip(st1.nextToken());
	    int k = ip(st1.nextToken());
	          
	    w.println((6*n-1)*k);
	         
	    int even = 2 ,odd = 1;
	    
	    for(int i=0;i<n;i++){
	    	w.printf("%d %d %d %d\n",k*even,k*odd,k*(odd+2),k*(odd+4));
	    	even += 2;
	    	if(i%2 != 0)
	    		even += 2;
	    	odd += 6;
	    }
	   
	    w.close(); 
	}
	
	public static int gcd(int a,int b){
		int temp=0;
		while(b!=0){
			temp = b;
			b = a%b;
			a = temp;
		}
		return a;
	}
	
	public static int ip(String s){
		return Integer.parseInt(s);
	}
}