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

#define ll long long
#define bug(a) cout << #a << " : " << a << endl;

void solve(){
	int n;	cin >> n;
	string s;	cin >> s;

	string tar = "SeriousOJ";
	int idx = 0;
	int cnt = 0;
	for(int i = 0; i < n; i++){
		if ( idx == 9 ) break;
		if (s[i] == tar[idx]){
			idx++;
			cnt++;
		}
	}

	cout << (cnt == tar.size() ? "YES" : "NO") << '\n';
}	

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	int tc = 1, cs = 0;
	cin >> tc;

	while(tc--){
		//cout << "Case # " << ++cs << ": " ;
		solve();
	}

}