import java.util.*

fun main(args: Array<String>) {
  val sc = Scanner(System.`in`)
  val k = sc.nextLong()
  val a = sc.nextLong()
  val b = sc.nextLong()

  val kMax = 1 + k

  val tmp = Math.max(0, (k-(a-1L))/2L)
  val tmpMax = (b-a) * tmp + (k-tmp * 2) + 1


  val max = Math.max(kMax, tmpMax)
  println(max)
}