using System;
using System.IO;
using System.Linq;
using System.Collections.Generic;
using System.Text;

public class Program
{

    public void Proc()
    {
        long cost1 = int.Parse(Reader.ReadLine());
        long cost2 = int.Parse(Reader.ReadLine());

        int inputCount = int.Parse(Reader.ReadLine());

        Dictionary<int, int> yoyaku = new Dictionary<int, int>();
        for (int i = 0; i < inputCount; i++) {
            int num = int.Parse(Reader.ReadLine());
            if(yoyaku.ContainsKey(num)) {
                yoyaku[num]++;
            } else {
                yoyaku[num] = 1;
            }
        }

        long ans = (cost1 + cost2) * yoyaku.Select(a => a.Value - 1).Sum();
        Console.WriteLine(ans);

    }





    public class Reader
    {
        private static StringReader sr;
        public static bool IsDebug = false;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (sr == null)
                {
                    sr = new StringReader(InputText.Trim());
                }
                return sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
        private static string InputText = @"


30000
50000
5
402
402
605
605
605



";
    }

    public static void Main(string[] args)
    {
#if DEBUG
        Reader.IsDebug = true;
#endif
        Program prg = new Program();
        prg.Proc();
    }
}