object Main extends App {
  import scala.io.StdIn._


  val Array(k, a, b) = readLine.trim.split(' ').map(_.toLong)
  println(solve(k, a, b))
  def solve(k: Long, a: Long, b: Long): Long = {
    if (k < a) {
      k + 1
    }else {
      val restK = k - a + 1
      if (a + 2 < b) {
        a + restK / 2 * (b - a) + restK % 2
      }else {
        k + 1
      }
    }
  }
  implicit class Scope[T](val value: T) extends AnyVal {
    @inline def also(@inline func: T ⇒ Unit): T = {
      func(value)
      value
    }
    @inline def let[A](@inline func: T ⇒ A): A = func(value)
  }
}