#include <stdio.h>
#include <iostream>
#include <string>
#include <set>

using namespace std;

int main() {
    int P1,P2,N,i,y;
    set<int> x;
    cin >> P1 >> P2 >> N;
    for(i=0;i<N;i++){
        cin >> y;
        x.insert(y);
    }
    int z = x.size();
    cout << (N-z)*(P1+P2);
}