N = int(input())

s = set()
for v in "1234567890":
    s.add(v)

for i in range(N):

    A,B,C,D,R = input().split()

    nset = set()
    if R == "YES":
        for v in s:
            if v in [A,B,C,D]:
                nset.add(v)

    else:
        for v in s:
            if v not in [A,B,C,D]:
                nset.add(v)

    s = nset

print (list(s)[0])