#include <bits/stdc++.h>
#define rep(i, ss, ee) for (int i = ss; i < ee; ++i)
using namespace std;

void solve() {
  int N, p1, p2, r;
  cin >> p1 >> p2 >> N;
  map<int, int> m;
  rep(i, 0, N) {
    cin >> r;
    m[r]++;
  }
  int sum = 0;
  for (auto e : m)
    if (e.second > 1) sum += (e.second - 1);

  cout << (p1 + p2) * sum << endl;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
  getchar();
}