def scoring(seq)
  hash = {}.tap do |h|
    seq.each_with_index do |elem, index|
      h[elem] = index
    end
  end
  I.sum do |l, r, s|
    hash[l] < hash[r] ? s : 0
  end
end

N, M = gets.split.map(&:to_i)
I = (1..M).map { gets.split.map(&:to_i) }

puts Array.new(N) { |index| index }.permutation.map { |seq| scoring(seq) }.max