N = input()

candidate = set(xrange(10))

for i in xrange(N):
    A, B, C, D, R = raw_input().split()
    numbers = map(int, (A, B, C, D))
    
    if R == 'YES':
        for x in xrange(10):
            if not x in numbers:
                candidate.discard(x)
    else:
        for x in numbers:
            candidate.discard(x)

print candidate.pop()