let readIntArray () =
    stdin.ReadLine().Split(" ") |> Array.map int

()
|> readIntArray
|> fun [| a; b; k |] ->
    [| a .. b |]
    |> fun x ->
        Array.concat [ Array.take k x
                       x |> Array.rev |> Array.take k ]
    |> Array.sort
    |> Array.map string
|> String.concat "\n"
|> printfn "%s"
