import sys
input = sys.stdin.readline

N=int(input())
L=[]
for i in range(N):
    S=list(input().strip())

    if S==sorted(S):
        L.append(S)

DP=[0]*26

L.sort()

for s in L:
    init=ord(s[0])-97
    end=ord(s[-1])-97

    xx=DP[init]+len(s)

    for j in range(end,26):
        DP[j]=max(DP[j],xx)

print(max(DP))