// http://yukicoder.me/problems/11 open System let dprintfn fmt = Printf.kprintf Diagnostics.Debug.WriteLine fmt let bitcount n = let rec loop bits num = if bits = 0 then num else loop (bits &&& (bits-1)) (num+1) loop n 0 let solve N = let visited = Array.init (N+1) (fun _ -> false) let queue = new System.Collections.Generic.Queue() let rec bfs (q : System.Collections.Generic.Queue) = if q.Count = 0 then -1 else let i, cnt = q.Dequeue() if i = N then cnt else visited.[i] <- true let n = bitcount i if i+n <= N && not visited.[i+n] then q.Enqueue(i+n, cnt+1) if i-n >= 1 && not visited.[i-n] then q.Enqueue(i-n, cnt+1) bfs q queue.Enqueue(1,1) bfs queue [] let main argv = let N = Console.ReadLine() |> int solve N |> printfn "%d" 0