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

#define ll long long
constexpr int maxn = 2e5+2;

int n;
ll arr[maxn];

inline ll dw3(ll x)
{
  if(x < 3) return 0;
  return (x*(x-1)*(x-2))/6;
}

inline ll dw2(ll x)
{
  if(x < 2) return 0;
  return (x*(x-1))/2;
}

bool check(ll k)
{
  ll pref = 0, x;
  for(int i=1; i<=n; i++)
  {
    if(k-pref < 0) return 0;

    if(arr[i] == 0) x=0;
    else
    {
      ll l=0, r=k-pref;
      while(l < r)
      {
        ll mid=(l+r)/2;
        if((dw3(mid) + dw2(mid)*(k-mid) + mid*pref*(k-mid-pref)) >= arr[i]) r = mid;
        else l = mid+1;
      }
      if((dw3(l) + dw2(l)*(k-l) + l*pref*(k-l-pref)) >= arr[i]) x=l;
      else return 0;
    }
    pref += x;
    if(k-pref < 0) return 0;
  }
  return 1;
}

int main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0); cout.tie(0);

  int t; cin >> t;
  while(t--)
  {
    cin >> n; ll lb=0, ub=0, sum=0;
    for(int i=1; i<=n; i++)
    {
      cin >> arr[i]; sum += arr[i];
      ll tmp=0;
      while(dw3(tmp) < arr[i]) tmp++;
      ub += tmp;
    }
    while(dw3(lb) < sum) lb++; 
    
    ll l=lb,r=min(ub,200008LL);
    while(l < r)
    {
      ll mid=(l+r)/2;
      if(check(mid)) r = mid;
      else l = mid+1;
    }
    cout << l << '\n';
  }
}