import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

N = int(input())
cand = []
for _ in range(N):
    S = [ord(s) - 97 + 1 for s in input().rstrip()]
    L = len(S)
    ok = True
    for i in range(L-1):
        if S[i] > S[i+1]:
            ok = False
            break
    if not ok:
        continue
    cand.append((S[0], S[-1], L))

cand.sort()
dp = [0] * 27
for s, t, l in cand:
    ndp = dp.copy()
    for x in range(s+1):
        ndp[t] = max(ndp[t], dp[x] + l)
    dp = ndp
print(max(dp))