n = int(input())
from collections import defaultdict

counts = defaultdict(int)
for _ in range(n):
    s = input().strip()
    num = len(s) - 2
    counts[num] += 1

max_count = max(counts.values(), default=0)
candidates = [k for k, v in counts.items() if v == max_count]
result = max(candidates)

print(result)