# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	N = int(input())
	A = [0] * 1001
	for i in range(N):
		s = input()
		n = len(s) - 2
		A[n] += 1

	val = 0
	ans = 0
	for i in range(1001):
		if A[i] >= val:
			ans = i
			val = A[i]

	print(ans)

if __name__ == '__main__':
	main()