import java.io.*; import java.util.*; import java.util.stream.*; public class Main { public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); int m = sc.nextInt(); int x = sc.nextInt(); HashMap> questions = new HashMap<>(); for (int i = 0; i < n; i++) { int a = sc.nextInt(); int b = sc.nextInt(); if (!questions.containsKey(b)) { questions.put(b, new ArrayList<>()); } questions.get(b).add(a); } ArrayList total = new ArrayList<>(); for (ArrayList list : questions.values()) { Collections.sort(list); list.add(list.remove(list.size() - 1) + x); total.addAll(list); } Collections.sort(total); long[] sums = new long[n + 1]; for (int i = 1; i <= n; i++) { sums[i] = sums[i - 1] + total.get(total.size() - i); } int k = sc.nextInt(); long ans = 0; for (int i = 0; i < k; i++) { ans += sums[sc.nextInt()]; } System.out.println(ans); } } class Utilities { static String arrayToLineString(Object[] arr) { return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n")); } static String arrayToLineString(int[] arr) { return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new)); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public int[] nextIntArray() throws Exception { return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }