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 Python (3.4.3) (judge verdict: Wrong Answer)

# coding: utf-8
# Your code here!
import copy
N,K=map(int,input().split())
lis=[]
lis2=[]
lis3=[]
ans=0
cnt=0
m=0
for i in range(1,N+1):
    now=i
    count=N-i+1
    while count!=0:
        if (i+now)%K==0:
            lis.append([i,now])
        now+=1
        count=count-1
print(lis)
for j in range(len(lis)):
    for k in range(1,N+1):
        if (lis[j][0]+k)%K==0 and (lis[j][1]+k)%K==0:
            lis2.append(copy.copy(lis[j]))
            lis2[cnt].append(k)
            cnt+=1
print(lis2)
for l in range(len(lis2)):
    lis3.append([lis2[l][0],lis2[l][1],lis2[l][2]])
    lis3.append([lis2[l][0],lis2[l][2],lis2[l][1]])
    lis3.append([lis2[l][1],lis2[l][0],lis2[l][2]])
    lis3.append([lis2[l][1],lis2[l][2],lis2[l][0]])
    lis3.append([lis2[l][2],lis2[l][0],lis2[l][1]])
    lis3.append([lis2[l][2],lis2[l][1],lis2[l][0]])
def get_unique_list(seq):
    seen = []
    return [x for x in seq if x not in seen and not seen.append(x)]
print(lis3)
l_2d_unique = get_unique_list(lis3)

print(len(l_2d_unique))