#include <bits/stdc++.h>
using namespace std;
template <class T = int>
inline T readInt();
template <class T>
inline void writeInt(T x, char end = 0);
int solve() {
  int n = readInt();
  vector<int> zeroes, a(n);
  zeroes.reserve(n);
  for (int i = 0; i < (int)(n); i++) {
    a[i] = readInt();
    if (!a[i]) zeroes.push_back(i);
  }
  int zn = zeroes.size();
  if (zn < 2) return 0;
  int mid = zeroes[zn / 2], ans = 0;
  vector<int> first(n + 1);
  priority_queue<pair<int, int>> s;
  for (int i = 0; i < (int)(mid); i++) first[a[i]] = i;
  for (int i = mid; i < n; i++)
    if (!a[i]) {
      if (s.size()) {
        first[s.top().second] = -1, ans++;
        s.pop();
      }
    } else if (first[a[i]] >= 0) {
      s.push({-first[a[i]], a[i]});
      first[a[i]] = -2;
    }
  for (int cnt = 0, i = mid - 1; i >= 0; i--) {
    if (!a[i]) {
      if (cnt) cnt--, ans++;
    } else if (first[a[i]] != -1)
      cnt++, first[a[i]] = -1;
  }
  return min(ans, zn / 2);
}
int main() {
  ios_base::sync_with_stdio(0), cin.tie(0);
  int t = readInt();
  while (t--) writeInt(solve(), '\n');
}
static const int buf_size = 4096;
inline int getChar() {
  static char buf[buf_size];
  static int len = 0, pos = 0;
  if (pos == len) pos = 0, len = fread(buf, 1, buf_size, stdin);
  if (pos == len) return -1;
  return buf[pos++];
}
inline int readChar() {
  int c = getChar();
  while (c <= 32) c = getChar();
  return c;
}
template <class T>
inline T readInt() {
  int s = 1, c = readChar();
  T x = 0;
  if (c == '-') s = -1, c = getChar();
  while ('0' <= c && c <= '9') x = x * 10 + c - '0', c = getChar();
  return s == 1 ? x : -x;
}
static int write_pos = 0;
static char write_buf[buf_size];
inline void writeChar(int x) {
  if (write_pos == buf_size)
    fwrite(write_buf, 1, buf_size, stdout), write_pos = 0;
  write_buf[write_pos++] = x;
}
template <class T>
inline void writeInt(T x, char end) {
  if (x < 0) writeChar('-'), x = -x;
  char s[24];
  int n = 0;
  while (x || !n) s[n++] = '0' + x % 10, x /= 10;
  while (n--) writeChar(s[n]);
  if (end) writeChar(end);
}
inline void writeWord(const char *s) {
  while (*s) writeChar(*s++);
}
struct Flusher {
  ~Flusher() {
    if (write_pos) fwrite(write_buf, 1, write_pos, stdout), write_pos = 0;
  }
} flusher;
