N = int(input())

eye_num = [[i, 0] for i in range(1001)]

for i in range(N):
    eye = input()
    eye_len = len(eye) - 2
    eye_num[eye_len][1] += 1

eye_num = sorted(eye_num, reverse=True, key=lambda x: (x[1], x[0]))

print(eye_num[0][0])