# https://yukicoder.me/problems/no/1512
# No.1512 作文

def alp2num(x): return ord(x) - ord("a")  # a, b, c, ... => 0, 1, 2, ...


n = int(input())
S = [list(map(alp2num, list(input()))) for _ in range(n)]
S = [s for s in S if all(i <= j for i, j in zip(s, s[1:]))]
if len(S) == 0:
    print(0)
    exit()
S.sort()

# pos[i][j]:= iで始まりjで終わる文字列の最大の文字数。
pos = [[0] * 26 for _ in range(26)]
for s in S:
    if s[0] == s[-1]:
        pos[s[0]][s[-1]] += len(s)
    else:
        pos[s[0]][s[-1]] = max(pos[s[0]][s[-1]], len(s))

# # pos[x][x]をpos[x][y]達に加算する
# for i in range(26):
#     for j in range(26):
#         if i < j:
#             pos[i][j] += pos[i][i]

# dp[i]:=末尾がi以下の最大の文字数
dp = [0] * 26
dp[0] = pos[0][0]

for i in range(1, 26):
    for j in range(i + 1):
        dp[i] = max(dp[i], dp[j] + pos[j][i])

print(dp[-1])