import java.util.Scanner

object Main{
  val sc = new Scanner(System.in)

  def main(srgs: Array[String]):Unit = {

    val k = sc.nextLong
    val a = sc.nextLong
    val b = sc.nextLong


    val res =
      if (a >= b - 1) k + 1 // a >= b の場合、びすけっとの交換は無駄
      else { // a < b
        if (k <= a + 1) k + 1
        else {
          val l = k - ( a + 1 )
          if(l % 2 == 0) b + (b - a) * l / 2
          else b + (b - a) * (l / 2) + 1
        }
      }
    println(res)
 }
}