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).toArray
  var all = 0
  var newGenre = 0
  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.toLong - contestantCount(0)
  var result = 0L
  for i <- 1 to n do
    while newGenre < n && useGenre(problem(sortedWithQuality(newGenre))._2) do
      newGenre += 1
    while all < n && useProblem(sortedWithQuality(all)) do
      all += 1
    if newGenre == n then
      val h = sortedWithQuality(all)
      useProblem(h) = true
      result += problem(h)._1 * rest
    else if all == n then
      val h = sortedWithQuality(newGenre)
      useProblem(h) = true
      useGenre(problem(h)._2) = true
      result += (problem(h)._1 + x) * rest
    else
      val hi = sortedWithQuality(newGenre)
      val hj = sortedWithQuality(all)
      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)