第四题 暴力递归（40%）

bool cmp(pair<int, int> &a, pair<int, int> &b) {
    if (a.first == b.first)
        return a.second > b.second;
    else
        return a.first > b.first;
}

void helper(vector<pair<int, int>> x, int max_weight, int height, int &res, int idx, int max_l) {
    res = max(res, height);
    if (idx == x.size())
        return;
    if (x[idx].first < max_l && x[idx].second <= max_weight) {
        if (max_weight - x[idx].second < x[idx].second * 7)
            helper(x, max_weight - x[idx].second, height + 1, res, idx + 1, x[idx].first);
        else
            helper(x, x[idx].second * 7, height + 1, res, idx + 1, x[idx].first);
    }
    helper(x, max_weight, height, res, idx + 1, max_l);

}
int main() {
    int n;
    cin >> n;
    vector<int> L(n), W(n);
    for (int i = 0; i < n; i++)
        cin >> L[i];
    for (int i = 0; i < n; i++)
        cin >> W[i];
    vector<pair<int, int>> x;
    for (int i = 0; i < n; i++)
        x.push_back(make_pair(L[i], W[i]));
    sort(x.begin(), x.end(), cmp);
    int res = 0;
    helper(x, INT_MAX, 0, res, 0, INT_MAX);
    cout << res << endl;
    system("pause");
    return 0;
}