import scala.io.StdIn._
object Main extends App {
  val Array(n, a, b) = readLine.trim.split(' ').map(_.toLong)
  val positions = readLine.trim.split(' ').map(_.toInt)
  var sum = 0L
  for (p ← positions.indices.tail) {
    if ((positions(p) - positions(p - 1)) * a > + b) {
      sum += b
    }else {
      sum += (positions(p) - positions(p - 1)) * a
    }
  }
  println(sum)
}