import copy
N = int(input())
sl, YN = [],[]
sample = set(range(10))
for v in range(N):
    if v != 0:
        num_old = copy.deepcopy(num)
    l = list(input().split())
    nl = [int(i) for i in l[0:4]]
    num = set(nl)
    if l[4] == "NO":
        sample = sample - num
    elif v != 0:
        sample = num_old & num
    else:
        pass
sample = list(sample)
print(sample[0])