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

int main(){
	int T,N;
	cin >> T;
	for(int v=0;v<T;v++){
		cin >> N;
		int k=0,p=0;
		char s[N],l = ' ',r = ' ';
		scanf("%s",&s);
		for(int i=0;i<N;i++){
			if(s[i] != '-' && (i == 0 || s[i-1] == '-')){
				l =s[i];
			}
			if(s[i] != '-' && (i == N-1 || s[i+1] == '-')){
				r =s[i];
				if(l == r){
					if(r == 'K') k++;
					if(r == 'P') p++;
				}
			}
		}
		if(k >= p){
			cout << "K" << endl;
		} else {
			cout << "P" << endl;
		}
	}
}