n = read_line.to_i

dp = [0] * 26
(1..n).each do
  s = read_line.chars
	f = s.first - 'a'
	l = s.last - 'a'
  if s.each_cons(2).all? { |(i, j)| i.ord <= j.ord }
    dp[l] = {dp[l], (dp[..f].max? || 0) + s.size}.max
  end
end
puts dp.max