#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define dbg(a,b,c,d) cerr<<a<<"  "<<b<<"  "<<c<<"  "<<d<<endl;
#define kill(a) {cout<<a<<endl;continue;}
#define KILL(a) {cout<<a<<endl;return 0;}
#define debug cerr<<"Error Found"<<endl;
#define mem(a,b) memset(a,b,sizeof(a))
#define lcm(a, b) (a/__gcd(a,b))*b
#define w(t) cin>>t;while(t--)
#define pi  2 * acos(0.0)
#define endl "\n"
int t, cs = 0;
const int mxn = 2e5 + 3, mod = 1e9 + 7;

int32_t main()
{
   w(t)
   {
       int n;
       cin >> n;
       int ar[n];
       for(int i = 0; i < n; i++)cin >> ar[i];
       int mx = 0, last = n + 1;
       bool f = false;
       for(int i = 0; i < n; i++)
       {
           if(ar[i] == 3) mx = max(mx, i - last + 1);
           else if(ar[i] == 2)f = false, last = n + 1;
           else if(ar[i] == 1)
           {
               if(!f)last = i;
               f = true;
           }
       }
       cout << mx << endl;
   }
}