def main():
    N = int(input())
    
    yes = set([1, 2, 3, 4, 5, 6, 7, 8, 9, 0])
    no = set()
    
    for i in range(N):
        s = input()
        if s[8] == 'N':
            no = no | set(list(map(int, s[0:7].split(' '))))
        else:
            yes = yes & set(list(map(int, s[0:7].split(' '))))
    print(list(set(yes) - set(no))[0])

if __name__ == '__main__':
    main()