#include <bits/stdc++.h>
#define int long long 
using namespace std;

int32_t main() {
    int t;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;

        string s;
        cin >> s;

        string target = "SeriousOJ";
        int index = 0;
        bool ys = false;

        for (char c : s) {
            if (c == target[index]) {
                index++;
                if (index == target.size()) {
                    ys = true;
                    break;
                }
            }
        }

        if (ys) {
            cout << "YES" << endl;
        } else {
            cout << "NO" << endl;
        }
    }
}