# -*- coding: utf-8 -*-

def main():
    N = int(input())
    nums = list(range(10))

    for i in range(N):
        t = list(input().split())
        if t[4] == "YES":
            nums = list(set(nums) & set(map(int, t[:4])))
        elif t[4] == "NO":
            nums = list(set(nums) - set(map(int, t[:4])))

    print(str(nums[0]) + "\n")
    
if __name__ == '__main__':
    main()