ans=set(['0','1','2','3','4','5','6','7','8','9'])
n=int(input())

for i in range(n):
    len=input().split()
    if "NO"==len.pop(4):
        diff=set(len)
        ans=ans-diff
    else:
        diff=set(len)
        ans=ans&diff

print(ans.pop())