N = input()
ABCDR = []
yes = set()
no = set()
for i in range(0, 10):
    yes.add(i)
digit = [0] * 10
for i in range(N):
    text = raw_input().split()
    if(text[-1] == "YES"):
        for j in map(int, text[0:4]):
            digit[j] += 1
    else:
        for j in map(int, text[0:4]):
            yes.discard(j)
            digit[j] = -1145141919810
if (len(yes) == 1):
    print yes.pop()
else:
    print digit.index(max(digit))