#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
int main() {
	int a, b, c;
	cin >> a >> b >> c;
	vector<int> d(c);
	for (int i = 0; i < c; i++) {
		cin >> d[i];
	}
	sort(d.end() - c, d.end());
	int e = 0;
	for (int i = 0; i < c - 1; i++) {
		if (d[i] == d[i + 1]) {
			e++;
		}
	}
	cout << (a + b)*e << endl;
}