#include <stdio.h>

int solve(int N, char S[])
{
	int i, j, num[3] = {};
	for (i = 0; i < N; i = j + 1) {
		if (S[i] == '-') {
			j = i;
			continue;
		}
		for (j = i; j < N && S[j] != '-'; j++);
		j--;
		if (S[i] != S[j]) num[2]++;
		else if (S[i] == 'K') num[0]++;
		else num[1]++;
	}
	if (num[0] >= num[1]) return 1;
	else return 0;
}

int main()
{
	int T, N;
	char S[500001];
	scanf("%d", &T);
	while (T--) {
		scanf("%d", &N);
		scanf("%s", S);
		if (solve(N, S) != 0) printf("K\n");
		else printf("P\n");
	}
	fflush(stdout);
	return 0;
}