n = int(input())
L = []
for _ in range(n):
    S = input()
    flag = True
    for i in range(1, len(S)):
        if ord(S[i]) < ord(S[i - 1]):
            flag = False
            break
    if flag:
        L.append(S)

L.sort()
m = len(L)
if m == 0:
    print(0)
    exit()

F = [[] for _ in range(26)]
for i in range(m):
    f = ord(L[i][0]) - ord('a')
    F[f].append(i)

DP = [len(L[i]) for i in range(m)]
for i in range(m):
    l = ord(L[i][-1]) - ord('a')
    for j in range(l, 26):
        for idx in F[j]:
            if idx == i:
                continue
            DP[idx] = max(DP[idx], DP[i] + len(L[idx]))

print(max(DP))