#include<bits/stdc++.h>

using namespace std;
using ll=long long;
#define rep2(i, a, n) for(int i = (a); i < (n); i++)
#define rep(i, n) rep2(i,0,n)

int main(){
  cin.tie(nullptr);ios_base::sync_with_stdio(false);
  int a,b,n;
  cin>>a>>b>>n;
  int hoge,res=0;
  map<int,int> map;
  for(;n>0;n--){
    cin>>hoge;
    map[hoge]++;
  }
  for(auto itr = map.begin(); itr != map.end(); ++itr) {
      //cout<<"key="<<itr->first<<",val="<<itr->second<<"\n";
      res+=(itr->second-1)*(a+b);
  }
  cout<<res<<endl;
}