import java.util.Scanner

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

  val n = sc.nextInt()
  val a = sc.nextInt(); val b = sc.nextInt()

  val x = new Array[Int](n+1)
  for(i <- 1 to n)
    x(i) = sc.nextInt()

  var ans = 0L
  for(i <- 1 to n-1) {
    val now: Long = x(i+1) - x(i)
    ans += Math.min(now * a, b)
  }

  println(ans)
}
