#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define MOD 1000000007
#define vll vector<ll>
#define endl "\n"
#define all(v) v.begin(), v.end()
#define mem(a,b) memset(a, b, sizeof(a))
#define co(n) cout << n << endl
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define fr(x, n) for (int i = x; i < n; ++i)
#define fraction(x) cout << fixed << setprecision(x)
#define Baba_Yaga ios_base::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL);
const double eps = 1e-9;
const int N = 2e5+123;
ll gcd(ll a,ll b) { return __gcd(a,b); }
ll lcm(ll a,ll b) { return (a*b)/__gcd(a,b); }
int dx[] = {0, 0, +1, -1, +1, +1, -1, -1};
int dy[] = {+1, -1, 0, 0, +1, -1, +1, -1};
void solve()
{
ll n; cin >> n;
string s; cin >> s;
string k = "SeriousOJ";
ll k_size = k.size();
ll p = 0;
ll j = 0;
for(int i=0; i<n; i++)
{
if(s[i] == k[j])
{
j++;
if(j == k_size)
{
yes;
return;
}
}
}
no;
}
int main()
{
Baba_Yaga;
ll tc = 1; cin >> tc;
for(int i=1; i<=tc; i++)
{
// cout << "Case " << i << ": ";
solve();
}
}