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#ifdef DEBUG
#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#else
#define debug(...) 228
#endif

#define pb push_back

typedef long long ll;
typedef long double ld;
int tst;
int n;
const int maxN = 2e5 + 10;
ll a[maxN];
void solve() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    ll L = 0;
    ll R = 300 * n;
    while (R - L > 1) {
        ll mid = (L + R) / 2;
        ll left = 0;
        bool ok = true;
        for (int i = 1; i <= n; i++) {
            ll le = -1;
            ll ri = min(300LL, mid - left + 1);
            while (ri - le > 1) {
                ll cnt = (ri + le) / 2;
                ll score = (cnt * (cnt - 1) * (cnt - 2)) / 6;
                score += (cnt * (cnt - 1)) / 2 * (mid - cnt);
                score += cnt * left * (mid - left - cnt);
//                debug(score, le, ri, mid, left, cnt);
                if (score >= a[i]) ri = cnt;
                else le = cnt;
            }
//            debug(le, ri, mid, left);
            if (ri == mid - left + 1) {
                ok = false;
                break;
            }
            left += ri;
        }
        if (!ok) L = mid;
        else {
            R = mid;
        }
    }
    cout << R << '\n';
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    auto start = std::chrono::high_resolution_clock::now();
#ifdef DEBUG
    freopen("input.txt", "r", stdin);
#endif
    cin >> tst;
    while (tst--) solve();
    auto end = std::chrono::high_resolution_clock::now();
    std::cerr << "Execution Time: "
              << std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count()
              << " ms" << std::endl;
    return 0;
}