#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<(n); ++i)
#define rep2(i, s, n) for(int i=s; i<(n); ++i)
#define ALL(v) (v).begin(), (v).end()

using namespace std;

typedef long long ll;

template<typename T>
using priority_queue_rev = priority_queue<T, vector<T>, greater<T> >;

static const int INTINF = (2147483647 >> 1); // 10^9 + 5000
static const ll LLINF = (9223372036854775807 >> 1);
static const int MAX = 1e5+1;
static const ll MOD = 1e9+7;

namespace Kunitaka{
    template<
        typename TYPE,
        std::size_t SIZE
    >
    std::size_t array_length(const TYPE (&array)[SIZE])
    {
        return SIZE;
    }

    template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
    template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
}
using namespace Kunitaka;
namespace Printer{
    void br(){
        cout << endl;
    }

    void loop_cnt(int i){
        cout << "i = " << i << endl;
    }

    void loop_cnt(int i, int j){
        cout << "i = " << i << ", " << "j = " << j << endl;
    }

    template<class T>
    void print(T x){
        cout << x << endl;
    }

    template<class T, class S>
    void print(T x, S y){
        cout << x << "," << y << endl;
    }

    template<class T, class S, class U>
    void print(T x, S y, U z){
        cout << x << "," << y << "," << z << endl;
    }

    template<class T, class S>
    void print(pair<T, S> p){
        cout << p.first << ", " << p.second << endl;
    }

    template<
        typename TYPE,
        std::size_t SIZE
    >
    void print(const TYPE (&array)[SIZE]){
        int lim = array_length(array);
        for(int i=0; i<lim; i++){
            if(i) cout << " ";
            cout << array[i];
        }
        cout << endl;
    }

    template<class S>
    void print(vector<S> v){
        for(int i=0; i<v.size(); i++){
            if(i) cout << " ";
            cout<< v[i];
        }
        cout << endl;
    }

    template<class S>
    void print(vector<vector<S> > vv){
        for(int i=0; i<vv.size(); i++){
            for(int j=0; j<vv[i].size(); j++){
                if(j) cout << " ";
                cout << vv[i][j];
            }
            cout << endl;
        }
    }

    void yesno(bool x){
        if(x) cout << "Yes" << endl;
        else cout << "No" << endl;
    }
};
using namespace Printer;

void ans_p(bool yes){
    if(yes) cout << 'O';
    if(!yes) cout << 'X';
    cout << endl;
}

int main(int argc, const char * argv[]) {
    //提出時、消す----//
    //--------------//


    // input
    cout << fixed << setprecision(10);
    int T; cin >> T;
    rep(i, T){
        int N; cin >> N;
        string str; cin >>str;
        if(str.size() < 3){
            ans_p(false);
            continue;
        }
        str += "x";
        rep(i, N+1){
            if(i-1 >=0 && i+1 < str.size())
            if(str[i-1] == '-' && str[i] == '-' && str[i+1] == '-'){
                str[i] = 'o';
                if(i+2 < str.size()){
                    if(str[i+2] == 'o'){
                        str[i+1] = 'x';
                        continue;
                    }
                }
                if(i-2 >= 0){
                    if(str[i-2] == 'o'){
                        str[i-1] = 'x';
                        continue;
                    }
                }
            }
        }
        // print(str);
        bool ok = false;
        char a = str[0];
        char b = str[1];
        char c = str[2];
        char d = str[3];
        rep2(j, 3, N+1){
            a = str[j-3];
            b = str[j-2];
            c = str[j-1];
            d = str[j];
            if(a == 'o' && b == 'o' && c == '-') ok = true;
            if(a == '-' && b == 'o' && c == 'o') ok = true;
            if(a == '-' && b == 'o' && c == '-' && d == '-') ok = true;
            if(a == '-' && b == '-' && c == 'o' && d == '-') ok = true;
            if(a == 'o' && b == 'o' && c == 'o') ok = true;
            if(a == 'o' && b == '-' && c == 'o') ok = true;
        }
        ans_p(ok);
        // break;
    }
    
    
    return 0;
}