Problem:
Score : 700 points

Problem Statement

Given are positive integers N and K.

Determine if the 3N integers K, K+1, ..., K+3N-1 can be partitioned into N triples (a_1,b_1,c_1), ..., (a_N,b_N,c_N) so that the condition below is satisfied. Any of the integers K, K+1, ..., K+3N-1 must appear in exactly one of those triples.

For every integer i from 1 to N, a_i + b_i \leq c_i holds.

If the answer is yes, construct one such partition.

Constraints

1 \leq N \leq 10^5

1 \leq K \leq 10^9

Input

Input is given from Standard Input in the following format:

N K

Output

If it is impossible to partition the integers satisfying the condition, print -1. If it is possible, print N triples in the following format:

a_1 b_1 c_1
:
a_N b_N c_N

Sample Input 1

1 1

Sample Output 1

1 2 3

Sample Input 2

3 3

Sample Output 2

-1

Solution in PyPy3 (2.4.0) (judge verdict: Wrong Answer)

N,K = list(map(int,input().split()))

ans = []
flag=True
for i in range(K,(K+3*N-1)-(K+2*N-1)+1):
    if i>= K+2*N:
        flag=False
        break
    ans.append((i,i+2*N-K,2*i + 2*N - K))
for i in range((K+3*N-1)-(K+2*N-1)+1,K+N):
    if i>= K+2*N:
        flag=False
        break
    ans.append((i,i + K + N - ((K+3*N-1)-(K+2*N-1)+1),2*i + K + N - ((K+3*N-1)-(K+2*N-1)+1)))

if flag:
    for a in ans:
        print(*a)
else:
    print(-1)