# coding:utf-8

import statistics

n = int(input())

taro_list = []
yes_num = []
no_num = []

for i in range(n):
    taro_list.append(input().split())

for j in range(n):
    for k in range(4):
        if taro_list[j][4] == 'NO':
            no_num.append(taro_list[j][k])
        else:
            yes_num.append(taro_list[j][k])

if len(yes_num) == 0:
    ans = set(ans_num) - set(no_num)
    print(*ans)

elif len(no_num) == 0:
    ans = statistics.mode(yes_num)
    print(*ans)

elif len(yes_num) >= 1 and len(no_num) >= 1:
    a = []
    for l in yes_num:
        if yes_num.count(l) == 2:
            a.append(l)
        else:
            continue
    ans = set(a) - set(no_num)
    print(*ans)