n = int(input())
array = [list(map(str, input().split())) for _ in range(n)]
number = [[0,1,2,3,4,5,6,7,8,9],[0,0,0,0,0,0,0,0,0,0]]
max = 0

for num in range(n):
    if array[num][4] == 'YES':
        max += 1
        for i in range(4):
            number[1][int(array[num][i])] += 1

for i in range(10):
    if max == number[1][i]:
        print(number[0][i])
        break