Dreamoon and Sets (Codeforces 477B)
Tags: Math, math

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 si, sj 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.

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.

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 .

Sample Inputs:
1 1

2 2

Sample Outputs:
5
1 2 3 5

22
2 4 6 22
14 18 10 16

Solution (Python):
(n, k) = map(int, input().split())
print((6 * n - 1) * k)
for i in range(n):
    print(str((6 * i + 1) * k) + ' ' + str((6 * i + 2) * k) + ' ' + str((6 * i + 3) * k) + ' ' + str((6 * i + 5) * k))

Solution (Python):
import sys
import heapq

def gcd(a, b):
    while b != 0:
        (a, b) = (b, a % b)
    return a

def compatible(n, s):
    for m in s:
        if gcd(n, m) > 1:
            return False
    return True
if __name__ == '__main__':
    (n, k) = map(int, sys.stdin.readline().split())
    print(((n - 1) * 6 + 5) * k)
    for i in range(n):
        s = [6 * i + 1, 6 * i + 2, 6 * i + 3, 6 * i + 5]
        print(' '.join((str(k * i) for i in s)))

Solution (Python):
(n, k) = map(int, input().split())
l = [1, 2, 3, 5]
print((6 * n - 1) * k)
for i in range(n):
    for j in l:
        print((6 * i + j) * k, end=' ')
    print()