A9577. Dreamoon and Sets

Dreamoon likes to play with sets, integers and .  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 $s_{i}$ , $s_{j}$ from $S$ , .

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.

The single line of the input contains two space separated integers $n$ , $k$ ( $1<=n<=10000,1<=k<=100$ ).

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.

For the first example it's easy to see that set ${1,2,3,4}$ isn't a valid set of rank 1 since .