import os
import sys
from io import BytesIO, IOBase
# region fastio
BUFSIZE = 8192
class FastIO(IOBase):
    newlines = 0
 
    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None
 
    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()
 
    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()
 
    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)
 
 
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")
 
 
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline()
 
# ------------------------------

def RL(): return map(int, sys.stdin.readline().split())
def RLL(): return list(map(int, sys.stdin.readline().split()))
def N(): return int(input())
def S(): return input().strip()
def print_list(l):
    print(' '.join(map(str, l)))

# sys.setrecursionlimit(100000)
# import random
# from functools import reduce
# from functools import lru_cache
# from heapq import *
# from collections import deque as dq
import math
# import bisect as bs
# from collections import Counter
# from collections import defaultdict as dc

def find(x, now):
    if tree[now] < x: return -1
    if now >= nn: return now - nn 
    t = find(x, now << 1)
    if t >= 0: return t 
    return find(x, now << 1 | 1)

for _ in range(N()):
    n, _ = RL()
    a, x = RLL(), RLL()
    s = [0]
    for v in a: s.append(s[-1] + v)
    nn = 1 << (n + 1).bit_length()
    tree = [0] * nn + s + [0] * (nn - n - 1)
    for i in range(nn - 1, 0, -1):
        tree[i] = max(tree[i << 1], tree[i << 1 | 1])
    ans = []
    for v in x:
        if s[-1] <= 0 and tree[1] < v: 
            ans.append(-1)
            continue
        k = 0 if v <= tree[1] else math.ceil((v - tree[1]) / s[-1])
        ans.append(k * n + find(v - k * s[-1], 1) - 1)
    print_list(ans)