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 MAXN = 2500;
int n, k;
inline long long Read() {
  long long x = 0, f = 0;
  char c = getchar();
  while (!isdigit(c)) {
    f |= c == '-';
    c = getchar();
  }
  while (isdigit(c)) {
    x = (x << 1) + (x << 3) + (c ^ 48);
    c = getchar();
  }
  return f ? -x : x;
}
inline void Write(const long long &x) {
  if (x < 0) {
    putchar('-');
    Write(-x);
    return;
  }
  if (x > 9) {
    Write(x / 10);
  }
  putchar((x % 10) ^ 48);
  return;
}
signed main() {
  n = Read(), k = Read();
  Write((6 * n - 1) * k), putchar('\n');
  for (register int i = 1, j = 1; i <= n; ++i, j += 6) {
    Write(j * k), putchar(' '), Write((j + 1) * k), putchar(' '),
        Write((j + 2) * k), putchar(' '), Write((j + 4) * k), putchar('\n');
  }
  return 0;
}