def score2(elems):
    count = sum(elems)
    total = 0
    allowed = count-(count//4)
    for i in range(100, -1, -1):
        if allowed > elems[i]:
            total += i*elems[i]
            allowed -= elems[i]
        else:
            total += i*allowed
            return total
    return total


def main():
    ct = int(input())

    for _ in range(ct):
        input()
        me_ = [int(i) for i in input().split()]
        other_ = [int(i) for i in input().split()]

        me = [0 for i in range(101)]
        other = [0 for i in range(101)]

        for i in range(len(me_)):
            me[me_[i]] += 1
            other[other_[i]] += 1

        i=0
        while score2(me) < score2(other):
            me[100] += 1
            other[0] += 1
            i+=1

        print(i)
       
main()