n = int(input())
eye_dic = {}
max_eye = 0
max_count = 0
for i in range(n):
    eye=len(input())
    eye_dic[eye]=eye_dic.get(eye,0)+1
    if eye_dic[eye]>max_count:
        max_count=eye_dic[eye]
        max_eye=eye
    elif eye_dic[eye]==max_count:
        max_eye=max(max_eye,eye)
print(max_eye-2)