#include <iostream>
#include <vector>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <deque>
#include <climits>
#include <cmath>
#include <numeric>
#include <string>
#include <bitset>
#include <assert.h>
#include <iomanip>
using namespace std;
template <typename T>
using pqg = priority_queue<T, vector<T>, greater<T>>;
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
*/
/*
#include <bits/stdc++.h>
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define getrand(l, r) uniform_int_distribution<int>(l, r)(rng)
*/
const long long infl = 1e18 + 1;
const int inf = 1e9 + 1;
const int mod1 = 1e9 + 7;
const int mod2 = 998244353;
const long double eps = 1e-7;
const int mod = mod1;
int add(int a, int b) { return (a + b) % mod; }
int sub(int a, int b) { return (a - b + mod) % mod; }
int mul(int a, int b) { return (int)((long long)a * b % mod); }
int pwr(int a, int b = mod - 2)
{
int res = 1;
for(; b > 0; b >>= 1, a = mul(a, a))
if(b & 1)
res = mul(res, a);
return res;
}
template <typename T>
bool chmax(T &a, T b)
{
if(b > a)
{
a = b;
return true;
}
return false;
}
template <typename T>
bool chmin(T &a, T b)
{
if(b < a)
{
a = b;
return true;
}
return false;
}
void solve()
{
int n;
cin >> n;
string s;
cin >> s;
string t = "SeriousOJ";
for(int i = 0, j = 0; i < n; i++)
{
if(s[i] == t[j])
{
j++;
}
if(j == (int)t.size())
{
cout << "YES";
return;
}
}
cout << "NO";
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
cin >> t;
while (t--)
{
solve();
cout << (t ? "\n" : "");
}
}