#include<bits/stdc++.h>
#define ll long long int
using namespace std;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int tc=1,tc1=1;
    cin>>tc;
    up:
    while(tc--){
      ll n;
      string s;
      cin>>n>>s;
      string t="SeriousOJ";
      ll c=0;
      for(auto i:s){
        if(i==t[c]){
          c++;
        }
        if(c==9){
          cout<<"YES\n";
          goto up;
        }
      }
      cout<<"NO\n";
    }
}