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 bool uax(T &x, T y) {
  return (y > x) ? x = y, true : false;
}
template <typename T>
inline bool uin(T &x, T y) {
  return (y < x) ? x = y, true : false;
}
string to_string(char c) { return "'" + string(1, c) + "'"; }
string to_string(string s) { return '"' + s + '"'; }
string to_string(const char *s) { return to_string((string)s); }
template <typename A>
string to_string(A);
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ": " + to_string(p.second) + ")";
}
template <typename A>
string to_string(A v) {
  bool f = false;
  string r = "{";
  for (auto x : v) {
    if (f) r += ", ";
    r += to_string(x);
    f = true;
  }
  return r += "}";
}
template <typename A>
string to_string(vector<vector<A>> v) {
  string r;
  for (auto x : v) r += "\n" + to_string(x);
  return r;
}
int Nerr;
template <typename A>
string to_string(A *p) {
  return to_string(vector<A>(p, p + Nerr));
}
void err(istream_iterator<string>) { cerr << endl; }
template <typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
  cerr << *it << " =: " << to_string(a) << "; ";
  err(++it, args...);
}
template <typename T>
void kek(T ans) {
  cout << ans << endl;
  exit(0);
}
int const MOD = 1e9 + 7;
long long const INF = 1e18 + 42;
int32_t main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int n, k;
  cin >> n >> k;
  vector<long long> a(n << 2);
  long long r = -1;
  for (int i = 0; i < n; ++i) {
    a[i * 4] = r + 3;
    for (int j = 1; j < 4; ++j) {
      r += 2;
      a[i * 4 + j] = r;
    }
  }
  cout << r * k << '\n';
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < 4; ++j) {
      cout << a[i * 4 + j] * k << ' ';
    }
    cout << '\n';
  }
}