#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class t, class u>
void chmax(t& first, u second) {
  if (first < second) first = second;
}
template <class t, class u>
void chmin(t& first, u second) {
  if (second < first) first = second;
}
template <class t>
using vc = vector<t>;
template <class t>
using vvc = vc<vc<t>>;
using pi = pair<ll, ll>;
using vi = vc<ll>;
template <class t, class u>
ostream& operator<<(ostream& os, const pair<t, u>& p) {
  return os << "{" << p.first << "," << p.second << "}";
}
template <class t>
ostream& operator<<(ostream& os, const vc<t>& v) {
  os << "{";
  for (auto e : v) os << e << ",";
  return os << "}";
}
using uint = unsigned;
using ull = unsigned long long;
template <class t, size_t n>
ostream& operator<<(ostream& os, const array<t, n>& first) {
  return os << vc<t>(first.begin(), first.end());
}
template <ll i, class T>
void print_tuple(ostream&, const T&) {}
template <ll i, class T, class H, class... Args>
void print_tuple(ostream& os, const T& t) {
  if (i) os << ",";
  os << get<i>(t);
  print_tuple<i + 1, T, Args...>(os, t);
}
template <class... Args>
ostream& operator<<(ostream& os, const tuple<Args...>& t) {
  os << "{";
  print_tuple<0, tuple<Args...>, Args...>(os, t);
  return os << "}";
}
template <class t>
void print(t x, ll suc = 1) {
  cout << x;
  if (suc == 1) cout << "\n";
  if (suc == 2) cout << " ";
}
ll read() {
  ll i;
  cin >> i;
  return i;
}
vi readvi(ll n, ll off = 0) {
  vi v(n);
  for (ll i = ll(0); i < ll(n); i++) v[i] = read() + off;
  return v;
}
pi readpi(ll off = 0) {
  ll first, second;
  cin >> first >> second;
  return pi(first + off, second + off);
}
template <class T>
void print(const vector<T>& v, ll suc = 1) {
  for (ll i = ll(0); i < ll(v.size()); i++)
    print(v[i], i == ll(v.size()) - 1 ? suc : 2);
}
string readString() {
  string s;
  cin >> s;
  return s;
}
template <class T>
T sq(const T& t) {
  return t * t;
}
void yes(bool ex = true) {
  cout << "Yes"
       << "\n";
  if (ex) exit(0);
}
void no(bool ex = true) {
  cout << "No"
       << "\n";
  if (ex) exit(0);
}
void possible(bool ex = true) {
  cout << "Possible"
       << "\n";
  if (ex) exit(0);
}
void impossible(bool ex = true) {
  cout << "Impossible"
       << "\n";
  if (ex) exit(0);
}
constexpr ll ten(ll n) { return n == 0 ? 1 : ten(n - 1) * 10; }
const ll infLL = LLONG_MAX / 3;
const ll inf = infLL;
ll topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }
ll topbit(ll t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }
ll botbit(signed first) { return first == 0 ? 32 : __builtin_ctz(first); }
ll botbit(ll first) { return first == 0 ? 64 : __builtin_ctzll(first); }
ll popcount(signed t) { return __builtin_popcount(t); }
ll popcount(ll t) { return __builtin_popcountll(t); }
bool ispow2(ll i) { return i && (i & -i) == i; }
ll mask(ll i) { return (ll(1) << i) - 1; }
bool inc(ll first, ll second, ll c) { return first <= second && second <= c; }
template <class t>
void mkuni(vc<t>& v) {
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
}
ll rand_int(ll l, ll r) {
  static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
  return uniform_int_distribution<ll>(l, r)(gen);
}
template <class t>
void myshuffle(vc<t>& first) {
  for (ll i = ll(0); i < ll(ll(first.size())); i++)
    swap(first[i], first[rand_int(0, i)]);
}
template <class t>
ll lwb(const vc<t>& v, const t& first) {
  return lower_bound(v.begin(), v.end(), first) - v.begin();
}
vvc<ll> readGraph(ll n, ll m) {
  vvc<ll> g(n);
  for (ll i = ll(0); i < ll(m); i++) {
    ll first, second;
    cin >> first >> second;
    first--;
    second--;
    g[first].push_back(second);
    g[second].push_back(first);
  }
  return g;
}
vvc<ll> readTree(ll n) { return readGraph(n, n - 1); }
ll sub(ll n, ll m, vc<pi> input) {
  vector<vi> sejm(m + 1);
  vi cnt(m + 1, 0);
  for (ll i = ll(0); i < ll(n); i++) {
    ll l = input[i].first + 1, r = input[i].second;
    sejm[l].push_back(r);
    cnt[l]++;
  }
  for (ll i = m; i >= 1; i--) cnt[i - 1] += cnt[i];
  ll edgeL = -1, mn = cnt[0];
  for (ll i = ll(0); i < ll(m); i++) {
    mn = min(mn - 1, cnt[i + 1] - 1);
    if (mn < 0) break;
    edgeL = i;
  }
  priority_queue<ll> pq;
  for (ll i = m; i >= 0; i--) {
    if (i <= edgeL) pq.pop();
    for (auto t : sejm[i]) pq.push(t);
  }
  cnt.assign(m + 1, 0);
  while (!pq.empty()) {
    ll t = pq.top();
    pq.pop();
    cnt[t]++;
  }
  for (ll i = ll(0); i < ll(m); i++) cnt[i + 1] += cnt[i];
  ll edgeR = m;
  mn = cnt[m];
  for (ll i = m - 1; i >= 0; i--) {
    mn = min(mn - 1, cnt[i] - 1);
    if (mn < 0) break;
    edgeR = i;
  }
  return min(m, (edgeL + 1) + (m - edgeR));
}
void slv() {
  ll n;
  cin >> n;
  vi first = readvi(n);
  ll z = count(first.begin(), first.end(), 0);
  vi vs;
  for (auto v : first)
    if (v) vs.push_back(v);
  mkuni(vs);
  if (z <= 1) {
    print(0);
    return;
  }
  ll h = z / 2;
  ll x = -1, y = -1;
  vi lf(n, -1), rt(n, -1);
  {
    ll cnt = 0;
    for (ll i = ll(0); i < ll(n); i++) {
      if (first[i] == 0) {
        if (cnt == h - 1) x = i;
        cnt++;
        chmin(cnt, h);
      } else {
        lf[i] = cnt;
      }
    }
  }
  {
    ll cnt = 0;
    for (ll i = ll(n) - 1; i >= ll(0); i--) {
      if (first[i] == 0) {
        if (cnt == h - 1) y = i;
        cnt++;
        chmin(cnt, h);
      } else {
        rt[i] = cnt;
      }
    }
  }
  ll s = ll(vs.size());
  vc<pi> input(s, pi(-1, h));
  for (ll i = ll(y) - 1; i >= ll(0); i--)
    if (first[i]) {
      ll j = lwb(vs, first[i]);
      chmax(input[j].first, lf[i] - 1);
    }
  for (ll i = ll(x); i < ll(n); i++)
    if (first[i]) {
      ll j = lwb(vs, first[i]);
      chmin(input[j].second, h - rt[i]);
    }
  for (ll i = ll(0); i < ll(s); i++) chmax(input[i].second, input[i].first + 1);
  void(0);
  print(sub(s, h, input));
}
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  ll t;
  cin >> t;
  for (ll _ = ll(0); _ < ll(t); _++) slv();
}
