import itertools as iter
import collections as coll
import heapq as hq
import bisect as bis
from decimal import Decimal as dec
from functools import cmp_to_key
import math
import sys
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
sys.setrecursionlimit(10 ** 6)
inp = sys.stdin.readline
input = lambda : inp()[:-1]
getN = lambda : int(inp())
getNs = lambda : map(int, inp().split())
getList = lambda : list(map(int, inp().split()))
getStrs = lambda n : [input() for _ in [0] * n]
getEdges = lambda n : [[x - 1 for x in getNs()] for _ in [0] * n]
getWEdges = lambda n : [[x - (i < 2) for i, x in enumerate(getNs())] for _ in [0] * n]
def yexit(): print("Yes"); exit(0)
def nexit(): print("No"); exit(0)
pi = 3.141592653589793
mod = 1000000007
MOD = 998244353
INF = 4611686018427387903
dxs = [1, 0, -1, 0];  dys = [0, 1, 0, -1]
#di = coll.defaultdict(int)


"""
Main Code
"""

for _ in [0] * getN():
    n = getN()
    s = input()
    g = 0
    for ss in s.split('-'):
        if not(ss):
            continue
        g += (ss[0] == 'K' and ss[-1] == 'K') - (ss[0] == 'P' and ss[-1] == 'P')
    if(g >= 0):
        print('K')
    else:
        print('P')