N = gets.to_i
S = N.times.map { gets.chomp }
T = S.select { |s| s.chars.each_cons(2).all? { |a, b| a <= b } }.sort
dp = Array.new(26, 0)
D = 'a'.ord

T.each do |t|
  i = t[0].ord - D
  j = t[-1].ord - D
  v = t.size

  (0..i).to_a.reverse_each do |c|
    len = dp[c] + v

    if dp[j] < len
      dp[j] = len
    end
  end
end

puts dp.max