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 PYTHON):

Solution:

import sys, math
def rs():
    return sys.stdin.readline().strip()
def ri():
    return int(sys.stdin.readline().strip())
def ras():
    return list(sys.stdin.readline().strip())
def rai():
    return map(int,sys.stdin.readline().strip().split())

def raf():
    return map(float,sys.stdin.readline().strip().split())



def solve():
    n,k = rai()
    groups = [0]*n
    s = 1
    t = 0
    while t < n:
        group = []
        while len(group) < 4:
            if s%4 != 0 and s%6 != 0:
                group.append(s*k)
            s+=1
        groups[t] = " ".join(map(str,group))
        t += 1

    print (s-1)*k
    return "\n".join(groups)

print solve()