N, M = gets.split.map(&:to_i)
nums = []
E = Hash.new { |h, k| h[k] = [] }

M.times do
  b, c = gets.split.map(&:to_i)

  nums << b
  nums << c
  E[c] << b
end

nums.uniq!
nums.sort!
visited = Hash.new(false)
memo = Hash.new

nums.reverse.each do |root|
  next if visited[root]

  queue = []
  queue << root
  until queue.empty?
    v = queue.shift

    next if visited[v]
    visited[v] = true
    memo[v] = root

    E[v].each do |u|
      next if u > root

      queue << u
    end
  end
end

sum = N * (1 + N) / 2

nums.each do |n|
  if memo[n]
    sum += memo[n] - n
  end
end

puts sum