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

namespace ConsoleApplication6
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<string, int> aiueo = new Dictionary<string, int>();

            int P1 = int.Parse(Console.ReadLine());
            int P2 = int.Parse(Console.ReadLine());
            int N = int.Parse(Console.ReadLine());

            for(int i = 0; i < N; i++)
            {
                string num = Console.ReadLine();
                if (aiueo.ContainsKey(num))
                {
                    aiueo[num] += 1;
                }
                else
                {
                    aiueo[num] = 1;
                }
            }
            int money = P1 + P2;
            int sum = 0;
            foreach(string key in aiueo.Keys)
            {
                sum += (aiueo[key] - 1) * money;
            }
            Console.WriteLine(sum);
        }
    }
}