import sys
from typing import List

def clamp(v: int, l: int, r: int):
    return max(l, min(v, r))

def clamp_sum(v: int, l: List[int], r: List[int]):
    res = 0
    for i in range(len(l)):
        res += clamp(v, l[i], r[i])
    return res

def main(n: int, m: int, l: List[int], r: List[int]):
    if not (sum(l) <= m <= sum(r)):
        return -1
    
    if m == sum(l):
        return (m * m - sum(e * e for e in l)) // 2
    
    tl, tr = 0, 10 ** 9 + 10
    while abs(tr - tl) > 1:
        t = (tl + tr) // 2
        if clamp_sum(t, l, r) < m:
            tl = t
        else:
            tr = t

    t0, d = tl, m - clamp_sum(tl, l, r)

    x = 0
    for i in range(n):
        c = clamp(t0, l[i], r[i])
        if d > 0 and l[i] <= t0 < r[i]:
            c += 1
            d -= 1
        x += c * c
    
    return (m * m - x) // 2

if __name__ == '__main__':
    readline = sys.stdin.readline

    t = int(readline())
    answers = []
    for _ in range(t):
        n, m = map(int, readline().split())
        l = list(map(int, readline().split()))
        r = list(map(int, readline().split()))
        answers.append(main(n, m, l, r))
    print('\n'.join(map(str, answers)))