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 PYTHON3):

Solution:
import sys

def solve():
    n, k, = rv()
    res = list()
    cur = 1
    for i in range(n):
        while cur % 2 == 0: cur+=1
        res.append(((cur) * k, (cur + 1) * k, (cur + 2) * k, (cur + 4) * k))
        cur += 5
    print(res[-1][-1])
    print('\n'.join((' '.join(map(str, l))) for l in res))

#12 14 16 20
# 2 * 2 * 3   2 * 7   2 * 2 * 2 * 2   2 * 3 * 3
# 1 2 3 5
# 7 8 9 11
# 13
# 19
# 25
# 31

def prt(l): return print(' '.join(l))
def rv(): return map(int, input().split())
def rl(n): return [list(map(int, input().split())) for _ in range(n)]
if sys.hexversion == 50594544 : sys.stdin = open("test.txt")
solve()