let ``No.48 ロボットの操縦``() =

  let X = stdin.ReadLine() |> int
  let Y = stdin.ReadLine() |> int
  let L = stdin.ReadLine() |> int

  let direction x y = 
      match x, y with
      | _ , _ when y < 0 -> 2
      | _ , _ when y >= 0 && x <> 0 -> 1
      | 0 , _ -> 0
      | _ , _ -> 1

  let sum = direction X Y
  let sum = sum + abs(X / L) + if (X % L = 0) then 0 else 1
  let sum = sum + abs(Y / L) + if (Y % L = 0) then 0 else 1
  stdout.WriteLine sum

``No.48 ロボットの操縦``()