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#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define ALL(x) begin(x), end(x)
#define SZ(x) (int)(x).size()
#define st first
#define nd second
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;

#ifdef LOCAL
#define DTP(x, y)                                    \
    auto operator<<(auto &o, auto a)->decltype(y, o) \
    {                                                \
        o << "(";                                    \
        x;                                           \
        return o << ")";                             \
    }
DTP(o << a.first << ", " << a.second, a.second);
DTP(for (auto i : a) o << i << ", ", ALL(a));
void dump(auto... x) { ((cerr << x << ", "), ...) << '\n'; }
#define debug(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", dump(x)
#else
#define debug(...) 42
#endif

ll ch3(ll &val)
{
    return max(((val * (val - 1) * (val - 2)) / 6), ll(0));
}

ll ch2(ll &val)
{
    return max((val * (val - 1)) / 2, ll(0));
}

ll calc(ll &val, ll &pre, ll &sum)
{
    return ch3(val) + ch2(val) * (sum - val) + pre * (val) * (sum - pre - val);
}

void solve()
{
    int n;
    cin >> n;
    vi V(n);
    for (auto &a : V)
        cin >> a;
    ll beg = 1, en = ll(200) * n;
    while (beg < en)
    {
        ll s = (beg + en) / 2;
        ll sum = 0;
        bool works = 1;
        for (ll i = 0; i < n; i++)
        {
            // debug(i);
            ll cnt = 0;
            while (sum + cnt < s && calc(cnt, sum, s) < V[i])
                cnt++;
            if (sum + cnt == s && calc(cnt, sum, s) < V[i])
            {
                works = 0;
                break;
            }
            sum += cnt;
        }
        if (works)
            en = s;
        else
            beg = s + 1;
    }
    cout << beg << endl;
}

main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    int Z = 1;
    cin >> Z;
    while (Z--)
        solve();
}