import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.Set;

public class No00000586_Main {
	static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	public static void main(String[] args) throws IOException {
		int p1 = Integer.parseInt(br.readLine());
		int p2 = Integer.parseInt(br.readLine());
		int n = Integer.parseInt(br.readLine());
		Set<String> s = new HashSet<String>();
		int cnt = 0;
		for(int i = 0; i < n; i++) {
			String r = br.readLine();
			if(s.contains(r)) {
				cnt++;
			} else {
				s.add(r);
			}
		}
		System.out.println((p1 + p2) * cnt);
	}
}