let (k, a, b) = Scanf.sscanf (read_line ()) "%d %d %d" @@ fun k a b -> (k, a, b)

let () = Printf.printf "%d\n" @@ 
  if b < a then k + 1
  else max (k + 1) (a + (k - a + 1) / 2 * (b - a) + (k - a + 1) mod 2)