n = int(input())
lr = []
for _ in range(n):
    S = input()
    l = len(S)
    ok = True
    for i in range(l - 1):
        if S[i] > S[i + 1]:
            ok = False
            break
    if ok:
        lr.append((ord(S[0]) - 97, ord(S[-1]) - 97, l))

lr.sort(key = lambda x:(x[1], x[0]))
dp = [0] * 26
for l, r, x in lr:
    max_ = 0
    for i in range(l + 1):
        max_ = max(max_, dp[i])
    dp[r] = max(dp[r], max_ + x)
print(max(dp))