N = int(input())
ans = [True for _ in range(10)]
yes_cnt = 0
for _ in range(N):
    L = list(map(str,input().split()))
    check = [int(item) for item in L[:-1]]
    Answer = L[-1]
    if Answer == 'NO':
        for item in check:
            ans[int(item)] = False
    elif Answer == 'YES':
        if yes_cnt == 0:
            for item in check:
                ans[int(item)] = True
            yes_cnt += 1
        for idx,item in enumerate(ans):
            if idx not in check and item == True:
                ans[idx] = False
for idx,item in enumerate(ans):
    if item == True:
        print(idx)
        break