Submission #3282756

---

Source Code Expand

M = 1000000009
N = gets.to_i
xs = []
(0...N).each{
  x = gets.to_i
  xs << [x, 0]
}
(0...N).each{
  x = gets.to_i
  xs << [x, 1]
}
xs.sort!

ans = 1
box = 0
bt = nil
xs.each{ |x,t|
  #p [ans, box, bt, [x,t]]
  if !bt
    box = 1
    bt = t
    next
  end
  
  if t == bt
    box += 1
  else
    ans = (ans * box) % M
    box -= 1
    if box == 0
      bt = nil
    end
  end
}
p ans

Submission Info

Judge Result