import os
import sys
from io import BytesIO, IOBase
from bisect import bisect_left as binary

def main():
    for _ in range(int(input())):
        n,m=map(int,input().split())
        a=list(map(int,input().split()))
        x=list(map(int,input().split()))
        l=[0]*n
        l[0]=a[0]
        for i in range(1,n):
            l[i]=a[i]+l[i-1]
        sumwhole=l[n-1]
        # print(sumwhole,l)
        d=dict()
        for i,item in enumerate(l):
            if d.get(item)==None:
                d[item]=i
        # print(d)
        lst=sorted(list(d.keys()))
        ans=[]
        for item in x:
            temp=binary(lst,item)
            if temp <len(lst):
                ans.append(d[lst[temp]])
            else:
                if sumwhole <=0:
                    ans.append(-1)
                else:
                    temp1=item%sumwhole
                    temp=binary(lst,temp1)
                    if temp1==0:
                        ans.append(n*(item//sumwhole)-1)
                    else:
                        ans.append(n*(item//sumwhole)+d[lst[temp]])
                    # print(temp1,temp,d[lst[temp]])
                    # print(ans)
        print(*ans)





# 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().rstrip("\r\n")

# endregion

if __name__ == "__main__":
    main()
