Data commit

Task/Perfect-shuffle/F-Sharp/perfect-shuffle.fs

@@ -0,0 +1,15 @@
+let perfectShuffle xs =
+  let h = (List.length xs) / 2
+  xs
+  |> List.mapi (fun i x->(if i<h then i * 2 else ((i-h) * 2) + 1), x)
+  |> List.sortBy fst
+  |> List.map snd
+
+let orderCount n =
+  let xs = [1..n]
+  let rec spin count ys =
+    if xs=ys then count
+    else ys |> perfectShuffle |> spin (count + 1)
+  xs |> perfectShuffle |> spin 1
+
+[ 8; 24; 52; 100; 1020; 1024; 10000 ] |> List.iter (fun n->n |> orderCount |> printfn "%d %d" n)