1393C - Pinkie Pie Eats Patty Cakes

using namespace std;
using ii = pair<int, int>;
using vi = vector<int>;
int const NMAX = 1e5 + 11;
int n, a[NMAX], freq[NMAX];
set<ii, greater<ii>> ordered_freq;
int main(void)
{
    ios_base::sync_with_stdio(false), cin.tie(NULL);
    int t;
    cin >> t;
    while (t--)
    {
        cin >> n;
        memset(freq, 0, sizeof(freq));
        ordered_freq.clear();
        for (int i = 0; i < n; ++i)
            cin >> a[i], freq[a[i]]++;
        for (int i = 0; i < NMAX; ++i)
            if (freq[i] > 0)
                ordered_freq.emplace(freq[i], i);
        auto [ftop, xtop] = *ordered_freq.begin();
        int cnt = 0, acc = 0;
        for (auto [fi, i] : ordered_freq)
        {
            if (fi < ftop)
                break;
            ++cnt;
            acc += ftop;
        }
        cout << (n - acc) / (ftop - 1) + cnt - 1 << endl;
    }
    return 0;
}