#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll MOD = 1e9+7;

void solve() {
    ll n; string s; cin >> n >> s;
    string check = "SeriousOJ";
    ll cnt = 0;
    // transform(s.begin(), s.end(), s.begin(), ::tolower);
    for(ll i=0, j=0; i<s.size() && j<check.size(); ) {
        if(s[i] == check[j]) {
            i++; j++; cnt++;
        }
        else i++;
    }
    cout << (cnt == 9 ? "YES\n" : "NO\n");
    // cout << cnt << endl;
}

int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

    ll t = 1;
    cin >> t;
    while(t--) {
        solve();
    }
    return 0;
}