N = gets.to_s.to_i
a = 'a'.ord
S = [] of {Int32, Int32, Int32}

def good?(s)
    c = s[0]
    s.each_char.all? { |d|
        x = c <= d
        c = d
        x
    }
end

N.times do
    s = gets.to_s.chomp
    next unless good?(s)
    S << {s[0].ord - a, s[-1].ord - a, s.size}
end

S.sort!

ans = 0

A = Array.new(26, 0)

S.each do |t|
    f, l, s = t[0], t[1], t[2]
    x = A[f]
    y = x + s
    (l ... 26).each do |i|
        A[i] = y if y > A[i]
    end
end

puts A.max