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 fractions

used = set()
mn = 0
unused = []

def get_unused(ptr):
    global unused
    if ptr != -1 and ptr < len(unused):
        return unused[ptr]
    n = unused[-1] if unused else 0
    while 1:
        n += 1
        if n not in used:
            unused.append(n)
            return n
    
def get_another_set():
    global mn, unused
    mx = None
    ret = []
    unused = []
    
    ptrs = []
    for i in range(4):
        get_unused(i)
        ptrs.append(-1)
        
    while 1:
        ptrs[0] += 1
        a1 = get_unused(ptrs[0])
        if mx and ptrs[0] >= mx: break
        ptrs[1] = ptrs[0]
        while 1:
            ptrs[1] += 1
            a2 = get_unused(ptrs[1])
            if mx and ptrs[1] >= mx: break
            if fractions.gcd(a2, a1) != 1: continue
            ptrs[2] = ptrs[1]
            while 1:
                ptrs[2] += 1
                a3 = get_unused(ptrs[2])
                if mx and ptrs[2] >= mx: break
                if fractions.gcd(a3, a1) != 1: continue
                if fractions.gcd(a3, a2) != 1: continue
                ptrs[3] = ptrs[2]
                while 1:
                    ptrs[3] += 1
                    a4 = get_unused(ptrs[3])
                    if mx and ptrs[3] >= mx: break
                    if fractions.gcd(a4, a1) != 1: continue
                    if fractions.gcd(a4, a2) != 1: continue
                    if fractions.gcd(a4, a3) != 1: continue
                    mx = ptrs[3]
                    ret = [a1, a2, a3, a4]
                    break
    return ret
            
def main():
    global mn
    n, k = [int(x) for x in raw_input().split()]
    ll = [[1,2,3,5]]
    
    
    for j in range(1, n):
        ll.append([1+3*j+((j+1)%2), 1+6*j, 3+6*j, 5+6*j])
        
        
        
    print ll[-1][-1] * k
    for l in ll:
        l = [k*x for x in l]
        print '{} {} {} {}'.format(*l)
        
main()