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:
__author__ = 'neki'

import sys

#sys.stdin = open("sets.in", "r")

global primes, primeDiv

def gcdPrime(a, b):
    if b==0 or a==0:
        return 0 #not prime
    if b==1 or a==1:
        return 1 #prime
    if b>a:
        return gcdPrime(a, b%a)

    return gcdPrime(b, a%b)

def gcdPrimeSet(set, a):
    result = []
    if len(set) >= 4: #full set
        return [x for x in set]
    for i in set:
        if gcdPrime(i, a) == 0:
            result.append(i)
    return result

words = str(input()).split()

n = int(words[0])
k = int(words[1])

sets = []
for i in range(n):
    sets.append(set())

el = -1
for i in range(len(sets)):
    el += 2
    while len(sets[i]) < 4:
        if el % 2 == 0:
            el += 1
        sets[i].add(el)
        sets[i].add(el+1)
        sets[i].add(el+2)
        el += 4
        while len(gcdPrimeSet(sets[i], el)) > 0:
            el += 2
        sets[i].add(el)

print(k*el)
for s in sets:
    for i in range(4):
        print(k*s.pop(), end=" ")
    print()