Problem:
Score : 300 points

Problem Statement

You are given integers N and K. Find the number of triples (a,b,c) of positive integers not greater than N such that a+b,b+c and c+a are all multiples of K.
The order of a,b,c does matter, and some of them can be the same.

Constraints

1 \leq N,K \leq 2\times 10^5

N and K are integers.

Input

Input is given from Standard Input in the following format:

N K

Output

Print the number of triples (a,b,c) of positive integers not greater than N such that a+b,b+c and c+a are all multiples of K.

Sample Input 1

3 2

Sample Output 1

9

(1,1,1),(1,1,3),(1,3,1),(1,3,3),(2,2,2),(3,1,1),(3,1,3),(3,3,1) and (3,3,3) satisfy the condition.

Sample Input 2

5 3

Sample Output 2

1

Sample Input 3

31415 9265

Sample Output 3

27

Sample Input 4

35897 932

Sample Output 4

114191

Solution in PyPy3 (7.3.0) (judge verdict: Time Limit Exceeded)

def odd(N, K):
    count = 0
    for x in range(1, N + 1):
        if x % K == 0:
            for y in range(1, N + 1):
                if y % K == 0:
                    for z in range(1, N + 1):
                        if z % K == 0:
                            count += 1
    return count


def even(N, K):
    count = 0
    for x in range(1, N + 1):
        if x % K == 0:
            for y in range(1, N + 1):
                if y % K == 0:
                    for z in range(1, N + 1):
                        if z % K == 0:
                            count += 1
    for x in range(1, N + 1):
        if x % K == K // 2:
            for y in range(1, N + 1):
                if y % K == K // 2:
                    for z in range(1, N + 1):
                        if z % K == K // 2:
                            count += 1
    return count


if __name__ == "__main__":
    n, k = map(int, input().split())
    ans = 0
    if k % 2 == 0:
        ans = even(n, k)
    else:
        ans = odd(n, k)
    print(ans)