using System;
using System.Collections.Generic;

public class Program
{
    public void Proc() {
        Reader.IsDebug = false;
        int marcCount = int.Parse(Reader.ReadLine());
        int numMax = int.Parse(Reader.ReadLine());
        
        int tefuda = int.Parse(Reader.ReadLine());
        
        Dictionary<int, int> markDic = new Dictionary<int, int>();
        Dictionary<int, int> numDic = new Dictionary<int, int>();
        for(int i=0; i<tefuda; i++) {
            int[] inpt = Reader.GetInt();
            if(!markDic.ContainsKey(inpt[0])) {
                markDic.Add(inpt[0], 1);
            } else
            {
                markDic[inpt[0]]++;
            }
            if(!numDic.ContainsKey(inpt[1])) {
                numDic.Add(inpt[1], 1);
            } else
            {
                numDic[inpt[1]]++;
            }
        }
        long ans = 0;
        ans += (numDic.Count * marcCount);
        ans += (markDic.Count * numMax);
        ans -= (numDic.Count * markDic.Count);
        ans -= tefuda;
        Console.WriteLine(ans.ToString("####################################0"));
    }
    



    public class Reader {
        private static String InitText = @"



3
2
2
1 1
2 1



        ";
        
        private static System.IO.StringReader sr = null;
        
        public static bool IsDebug = true;
        
        public static string ReadLine() {
            if(IsDebug) {
                if(sr == null) {
                    sr = new System.IO.StringReader(InitText.Trim());
                }
                return sr.ReadLine();
            } else {
                return Console.ReadLine();
            }
        }
        public static int[] GetInt(char delimiter = ' ') {
            string[] inpt = ReadLine().Split(delimiter);
            int[] ret = new int[inpt.Length];
            for(int i=0; i<inpt.Length; i++) {
                ret[i] = int.Parse(inpt[i]);
            }
            return ret;
        }
    }
    public static void Main(string[] args)
    {
        Program prg = new Program();
        prg.Proc();
    }
}