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 = Hash.new(0)

T.each do |t|
  i = t[0]
  j = t[-1]

  ('a'..i).to_a.reverse_each do |c|
    len = dp[c] + t.size

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

values = dp.values

if values.empty?
  puts 0
else
  puts values.max
end