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;
template <typename T>
inline void read(T &x) {
  static char ch;
  bool f = 1;
  for (x = 0, ch = getchar(); !isdigit(ch); ch = getchar())
    if (ch == '-') f = 0;
  for (; isdigit(ch); x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar())
    ;
  x = f ? x : -x;
}
template <typename T>
void print(T x) {
  if (x < 0) x = -x, putchar('-');
  if (x > 9) print(x / 10);
  putchar(x % 10 + 48);
}
template <typename T>
inline void print(T x, char ap) {
  print(x);
  if (ap) putchar(ap);
}
template <typename T>
inline void chkmax(T &x, const T &y) {
  x = x < y ? y : x;
}
template <typename T>
inline void chkmin(T &x, const T &y) {
  x = x < y ? x : y;
}
int n, k;
int main() {
  read(n), read(k);
  print(k * (6 * n - 1), '\n');
  for (register int i = 0, _r = n - 1; i <= _r; ++i)
    print(k * (6 * i + 1), ' '), print(k * (6 * i + 2), ' '),
        print(k * (6 * i + 3), ' '), print(k * (6 * i + 5), '\n');
  return 0;
}