import bisect
import copy
import decimal
import fractions
import heapq
import itertools
import math
import random
import sys
import time
from collections import Counter,deque,defaultdict
from functools import lru_cache,reduce
from heapq import heappush,heappop,heapify,heappushpop,_heappop_max,_heapify_max
def _heappush_max(heap,item):
    heap.append(item)
    heapq._siftdown_max(heap, 0, len(heap)-1)
def _heappushpop_max(heap, item):
    if heap and item < heap[0]:
        item, heap[0] = heap[0], item
        heapq._siftup_max(heap, 0)
    return item
from math import gcd as GCD
read=sys.stdin.read
readline=sys.stdin.readline
readlines=sys.stdin.readlines
write=sys.stdout.write
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
#sys.set_int_max_str_digits(10**9)
def FindAnswer(arr):
    result = 0
    curMax = 0
    left = 0
    
    for i in range(len(arr)):
        curMax += arr[i]
        
        if curMax < 0:
            curMax = 0
            left = i + 1
        
        result = max(result, (i - left + 1) * curMax)
    
    return result

def correct(A):
    N=len(A)
    C=[0]+A
    for i in range(1,N+1):
        C[i]+=C[i-1]
    return max((r-l)*(C[r]-C[l]) for l in range(N) for r in range(l+1,N+1))

T=int(input())
for t in range(T):
    K,L=map(int,input().split())
    if 2000<=L:
        print(-1)
        continue
    C=1998
    S=K+1+C
    ans_lst=[-1]
    M=10**6
    for c in range(C):
        a=min(M,S)
        ans_lst.append(a)
        S-=a
    assert len(ans_lst)<=2*10**3
    print(len(ans_lst))
    print(*ans_lst)
    #print(len(ans_lst)*sum(ans_lst),(len(ans_lst)-1)*sum(ans_lst[1:]))
    #print(correct(ans_lst),FindAnswer(ans_lst))