import io.{StdIn => in}

object Main extends App {
  val Array(k, a, b) = in.readLine.split(" ").map(_.toLong)

  def f(acc:Long, k:Int):Long = {
    if(k < 2) acc
    else f(acc - a + b, k-2)
  }

  val res = {
    val k1 = k - (a-1)
    val r = k1 % 2
    f(a,k1.toInt) + r
  }
  val ans = math.max(res, k+1)

  println(ans)
}