#include <bits/stdc++.h>
using namespace std;
#define nl "\n"
#define pb push_back
#define pB pop_back
#define optimize()                    \
    ios_base::sync_with_stdio(false); \
    cin.tie(0);                       \
    cout.tie(0);
typedef long long ll;
const int mod = 1e9+7;
void solve()
{
    int n; cin>>n;
    string a; cin>>a;
    string b="SeriousOJ";
    int l=a.size(),j=0;
    for(int i=0; i<n; i++)
    {
        if(a[i]==b[j])
        {
            j++;
        }
    }
    if(j==9) cout<<"YES\n";
    else cout<<"NO\n";

}
int main()
{
    optimize();
    int t;
    cin>>t;
    //t=1;
    while(t--)
    {
        solve();
    }

    return 0;
}