using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yukicoder_586 {
    class Program {
        static void Main(string[] args) {
            int p1 = int.Parse(Console.ReadLine());
            int p2 = int.Parse(Console.ReadLine());
            int n = int.Parse(Console.ReadLine());
            int count = 0;
            int[] r = new int[n];
            for (int i = 0; i < n; i++) {
                r[i] = int.Parse(Console.ReadLine());
            }
            Array.Sort(r);
            for (int i = 1; i < n; i++) {
                if (r[i - 1] == r[i]) {
                    count++;
                }
            }
            Console.WriteLine(count * (p1 + p2));
            Console.ReadLine();
        }
    }
}