import scala.annotation.tailrec
import scala.collection.mutable
import scala.io.StdIn.*


@main def main =
  val Array(n, m, x) = readLine().split(' ').map(_.toInt)
  val problem = Array.fill(n){
    val Array(a, b) = readLine().split(' ').map(_.toInt)
    (a, b - 1)
  }
  val k = readLine().toInt
  val contestant = readLine().split(' ').map(_.toInt)
  val sortedWithQuality = (0 until n).sorted(Ordering.by[Int, Int](problem(_)._1).reverse).toList
  var all = sortedWithQuality
  var newGenre = sortedWithQuality
  val useGenre = Array.fill(m){false}
  val useProblem = Array.fill(n){false}
  val contestantCount = Array.fill(n + 1){0}
  for c <- contestant do
    contestantCount(c) += 1
  var rest = k - contestantCount(0)
  @tailrec def popNewGenre(rest: List[Int]): List[Int] =
    rest match
      case h::t if useGenre(problem(h)._2) => popNewGenre(t)
      case _ => rest
  @tailrec def popAll(rest: List[Int]): List[Int] =
    rest match
      case h::t if useProblem(h) => popAll(t)
      case _ => rest
  var result = 0L
  for i <- 1 to n do
    newGenre = popNewGenre(newGenre)
    all = popAll(all)
    (newGenre, all) match
      case (Nil, h::t) =>
        useProblem(h) = true
        result += problem(h)._1 * rest
      case (h::t, Nil) =>
        useProblem(h) = true
        useGenre(problem(h)._2) = true
        result += (problem(h)._1 + x) * rest
      case (hi::ti, hj::tj) =>
        if problem(hi)._1 + x < problem(hj)._1 then
          useProblem(hj) = true
          result += problem(hj)._1 * rest
        else
          useProblem(hi) = true
          useGenre(problem(hi)._2) = true
          result += (problem(hi)._1 + x) * rest
    rest -= contestantCount(i)
  println(result)