#include <bits/stdc++.h>

#pragma GCC optimize("Ofast")
using namespace std;

void solve(int cs) {
  int n;
  cin >> n;
  vector <int> a(n);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  int res = 0;
  for (int i = 0; i < n; i++) {
    if (a[i] == 1) {
      int j = i;
      for (; i < n; i++) {
        if (a[i] == 2) {
          break;
        } else if (a[i] == 3) {
          res = max(res, i - j + 1);
        }
      }
    }
  }
  cout << res << "\n";
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int tc = 1;
  cin >> tc;
  for (int cs = 1; cs <= tc; cs++) {
    solve(cs);
  }
  return 0;
}