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

vector<string> split(const string &s, char delim) {
    vector<string> ret;
    string tmp;
    for(char c : s){
        if(c == delim){
            if(!tmp.empty()){
                ret.push_back(tmp);
            }
            tmp.clear();
        }
        else {
            tmp.push_back(c);
        }
    }
    if(!tmp.empty()){
        ret.push_back(tmp);
    }
    return ret;
}


char solve(int n, string& s){
    vector<string> vec = split(s, '-');
    int score = 0;
    for(string& ss : vec){
        score += (ss[0] == 'K' || ss[ss.size() - 1] == 'K');
        score -= (ss[0] == 'P' || ss[ss.size() - 1] == 'P');
    }
    return (score >= 0) ? 'K' : 'P';
}


int main(){
    int t;  cin >> t;

    for(int i = 0; i < t; ++i){
        int n;  cin >> n;
        string s;   cin >> s;
        cout << solve(n, s) << endl;
    }

    return 0;
}