import sys
input = lambda: sys.stdin.readline().rstrip()
N = int(input())
X = [0] * 26
Y = [[0] * 26 for _ in range(26)]
for _ in range(N):
    S = [ord(a) - 97 for a in input()]
    for a, b in zip(S, S[1:]):
        if a > b:
            break
    else:
        l = S[0]
        r = S[-1]
        m = len(S)
        if l == r:
            X[l] += m
        else:
            Y[l][r] = max(Y[l][r], m)

Z = [0] * 27
for i in range(26):
    Z[i] += X[i]
    for j in range(i + 1, 26):
        Z[j] = max(Z[j], Z[i] + Y[i][j])
print(max(Z))