#include <bits/stdc++.h>
using namespace std;
template <class c>
struct rge {
  c b, e;
};
template <class c>
rge<c> range(c i, c j) {
  return rge<c>{i, j};
}
template <class c>
auto dud(c *x) -> decltype(cerr << *x, 0);
template <class c>
char dud(...);
struct deb {
  template <class c>
  deb &operator<<(const c &) {
    return *this;
  }
};
template <class T>
T &chmin(T &a, const T &b) {
  return a = min(a, b);
}
template <class T>
T &chmax(T &a, const T &b) {
  return a = max(a, b);
}
const long long dx[8] = {0, 1, -1, 0, 1, 1, -1, -1};
const long long dy[8] = {1, 0, 0, -1, 1, -1, -1, 1};
const long long mod = 1e9 + 7;
inline long long add(long long a, long long b) {
  return ((a % mod) + (b % mod)) % mod;
}
inline long long sub(long long a, long long b) {
  return ((a % mod) - (b % mod) + mod) % mod;
}
inline long long mul(long long a, long long b) {
  return ((a % mod) * (b % mod)) % mod;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
  for (auto &v : vec) is >> v;
  return is;
}
const double PI = acos(-1.0);
const long long inf = 1e18;
const long long maxn = 1e3 + 5;
bool check(vector<long long> &arr, long long d, long long mx,
           long long maxCount) {
  long long n = (long long)arr.size();
  long long partCount = mx - 1;
  long long partLength = d - (maxCount - 1);
  long long emptySlots = partCount * partLength;
  long long availableTasks = n - mx * maxCount;
  long long idles = max(0LL, emptySlots - availableTasks);
  if (idles > 0) return false;
  return true;
}
void solve() {
  long long n;
  cin >> n;
  vector<long long> arr(n);
  cin >> arr;
  sort(arr.begin(), arr.end());
  long long l = 0;
  long long h = n - 2;
  map<long long, long long> mp;
  long long mx = 0;
  for (auto v : arr) {
    mp[v]++;
    mx = max(mx, mp[v]);
  }
  long long cnt = 0;
  for (auto i : mp) {
    if (i.second == mx) cnt++;
  }
  long long ans = 0;
  while (l <= h) {
    long long m = l + (h - l) / 2;
    bool ok = check(arr, m, mx, cnt);
    if (ok) {
      ans = m;
      l = m + 1;
    } else {
      h = m - 1;
    }
  }
  cout << ans << "\n";
}
signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long t = 1;
  cin >> t;
  for (long long tt = 1; tt <= t; tt++) {
    solve();
  }
}
