n = int(input())
ng, ok = [], []
for _ in range(n):
    l = list(input().split())
    for i in range(4):
        c = int(l[i])
        if l[-1]=='YES':
            if c not in ok:
                ok.append(c)
        else:
            if c not in ng:
                ng.append(c)

ans = []
for i in range(1, 10):
    if i not in ng:
        ans.append(i)
if len(ans)==1:
    print(ans[0])
else:
    for a in ans:
        if a in ok:
            print(a)