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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())

template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}

template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e;
    return o << '}';
}

#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n';
#else
#define debug(...) {}
#endif


LL rt_3(LL n) {
    LL l = 1, r = n;
    while (l < r) {
        LL mid = (l + r + 1) / 2;
        if (mid * mid * mid > n)
            r = mid - 1;
        else
            l = mid;
    }

    return l;
}

LL choose_3(LL n) {
    return n * (n - 1) * (n - 2) / 6;
}

LL choose_2(LL n) {
    return n * (n - 1) / 2;
}


void solve() {
    int n;
    cin >> n;
    LL mx = 0;
    vector<LL> a(n);
    REP(i, n) {
        cin >> a[i];
        mx = max(mx, a[i]);
    }

    LL l = 1, r = mx * n + 2;
    while (l < r) {
        debug(l, r);
        LL mid = (l + r) / 2;
        LL left = 0, total = mid;

        REP(i, n) {
            if (a[i] == 0)
                continue;

            LL lc = 1, rc = 2 * rt_3(a[i]) + 4;
            rc = min(rc, total - left);
            LL curr_sum = choose_3(rc) + choose_2(rc) * (total - rc) +
                rc * left * (total - left - rc);
            if (curr_sum < a[i]) {
                left = mid + 1;
                break;
            }

            while (lc < rc) {
                LL c = (lc + rc) / 2;
                debug(lc, rc, c);
                curr_sum = choose_3(c) + choose_2(c) * (total - c) +
                    c * left * (total - left - c);

                // debug(curr_sum);
                if (curr_sum >= a[i])
                    rc = c;
                else
                    lc = c + 1;
            }

            debug(rc);

            left += rc;
        }

        if (left <= mid)
            r = mid;
        else
            l = mid + 1;
    }

    cout << l << '\n';
}


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

    int q;
    cin >> q;
    while (q--)
        solve();

    return 0;
}