import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int p1 = sc.nextInt();
    int p2 = sc.nextInt();
    int n = sc.nextInt();
    HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();
    for(int i = 0; i < n; i++) {
      int r = sc.nextInt();
      if(map.containsKey(r)) {
        map.put(r, map.get(r) + 1);
      } else {
        map.put(r, 1);
      }
    }
    int ans = 0;
    for(int r : map.keySet()) {
      ans += (map.get(r) - 1);
    }
    ans = (ans * (p1 + p2));
    System.out.println(ans);
  }
}