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;
const int INF = 0x3f3f3f3f;
const double eps = 1e-9;
const double PI = (4.0 * atan(1.0));
const int maxn = 10010;
const int maxl = 1000 + 20;
const long long mod = 1000000007;
int n, m, k;
int vis[maxn];
set<int> s;
vector<int> v;
int ans;
int main() {
  while (cin >> n >> k) {
    printf("%d\n", (6 * n - 1) * k);
    for (int i = 1; i <= n; ++i) {
      int j = 6 * i - 1;
      printf("%d %d %d %d\n", (j - 4) * k, (j - 2) * k, (j - 1) * k, j * k);
    }
  }
}