# frozen_string_literal: true
in_h, in_w = gets.chomp.split.map(&:to_i)
in_a, in_b = gets.chomp.split.map(&:to_i)
in_r1, in_c1, in_r2, in_c2 = gets.chomp.split.map(&:to_i)
in_p, in_q = gets.chomp.split.map(&:to_i)

def distance_between(a, b, c, d)
  (a - c).abs + (b - d).abs
end

min = 10**10
(in_r1..in_r2).each do |r|
  (in_c1..in_c2).each do |c|
    min = [
      distance_between(in_a, in_b, r, c) + distance_between(r, c, in_p, in_q),
      min
    ].min
  end
end

puts min + distance_between(in_p, in_q, in_a, in_b)