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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
typedef struct {
  int sum, suf, pre, max;
} Node;
int toint(const string &s) {
  stringstream ss;
  ss << s;
  int x;
  ss >> x;
  return x;
}
const int N = 2e5 + 10;
const int inf = 1e9;
const int lim = 1e18 + 1;
const int mod = 998244353;
const double pi = 3.141592653589793238462643383;
const int M = 1e6 + 10;
const double Phi = 1.618033988749894;
const int logn = 20;
const double phi = 0.618033988749894;
const double root5 = 2.236067977;
int n, k;
int main() {
  scanf("%d%d", &n, &k);
  int m = (6 * n - 1) * k;
  cout << m << endl;
  for (int i = 0; i < n; ++i) {
    cout << ((6 * i + 1) * k) << " " << ((6 * i + 2) * k) << " "
         << ((6 * i + 3) * k) << " " << ((6 * i + 5) * k) << endl;
  }
  return 0;
}