#include <bits/stdc++.h>
using namespace std;

using int64 = long long;
using i128 = __int128_t;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int T;
    cin >> T;

    while (T--) {
        int N;
        long long K;
        cin >> N >> K;

        vector<long long> A(N), B(N), C(N), D(N);
        for (int i = 0; i < N; i++) cin >> A[i];
        for (int i = 0; i < N; i++) cin >> B[i];
        for (int i = 0; i < N; i++) cin >> C[i];
        for (int i = 0; i < N; i++) cin >> D[i];

        // key = buy cost, value = count of stored jewels with that cost
        map<long long, long long> mp;
        long long total = 0;   // total stored jewels
        i128 ans = 0;          // profit over initial 10^100

        for (int i = 0; i < N; i++) {
            // 1) Buy candidates
            mp[A[i]] += B[i];
            total += B[i];

            // 2) Sell up to D[i], always from cheapest profitable jewels
            long long remSell = D[i];
            while (remSell > 0 && !mp.empty()) {
                auto it = mp.begin();
                long long cost = it->first;
                long long cnt  = it->second;

                if (cost >= C[i]) break;  // no profitable sell anymore

                long long x = min(remSell, cnt);
                ans += (i128)x * (C[i] - cost);

                remSell -= x;
                total -= x;
                it->second -= x;
                if (it->second == 0) mp.erase(it);
            }

            // 3) Keep only cheapest K jewels for future; discard expensive extras
            long long excess = total - K;
            while (excess > 0) {
                auto it = prev(mp.end());
                long long cnt = it->second;
                long long x = min(excess, cnt);

                it->second -= x;
                total -= x;
                excess -= x;
                if (it->second == 0) mp.erase(it);
            }
        }

        // print i128
        if (ans == 0) {
            cout << 0 << '\n';
        } else {
            string s;
            while (ans > 0) {
                int digit = (int)(ans % 10);
                s.push_back(char('0' + digit));
                ans /= 10;
            }
            reverse(s.begin(), s.end());
            cout << s << '\n';
        }
    }

    return 0;
}