using System;
using System.Collections.Generic;
using System.Linq;
using static System.Console;
using static System.Math;

class MainClass : Scanner
{
    static void Main()
    {
        var (H, W, M) = ReadTuple<int,int,int>();
        var hw = new int[M][];
        for (int i = 0; i < M; i++)
        {
            hw[i] = RInts();
        }

        var Hs = new int[300001];
        var Ws = new int[300001];
        var Pos = new HashSet<(int, int)>();
        for (int i = 0; i < M; i++)
        {
            var pos = hw[i];
            Hs[pos[0]]++;
            Ws[pos[1]]++;
            Pos.Add((pos[0], pos[1]));
        }

        int maxH = Hs.Max();
        int maxW = Ws.Max();
        var maxHs = new HashSet<int>();
        var maxWs = new HashSet<int>();
        for (int i = 0; i < M; i++)
        {
            var p = hw[i];
            if (Hs[p[0]] == maxH) maxHs.Add(p[0]);
            if (Ws[p[1]] == maxW) maxWs.Add(p[1]);
        }
        int ans = maxH+maxW-1;
        if (maxHs.Count * maxWs.Count > 400000) ans = maxH + maxW;
        else
        {
            foreach (var h in maxHs)
            {
                foreach (var w in maxWs)
                {
                    if (Pos.Contains((h,w))) continue;
                    ans = maxH + maxW;
                    goto END;
                }
            }
        }
    END:;
        WriteLine(ans);
    }
}



class Scanner
{
    public static string RString() => Console.ReadLine();
    public static int RInt() => ReadTuple<int>();
    public static long RLong() => ReadTuple<long>();
    public static double RDouble() => ReadTuple<double>();

    public static string[] RStrings() => Console.ReadLine().Split();
    public static int[] RInts() => Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
    public static long[] RLongs() => Array.ConvertAll(Console.ReadLine().Split(), long.Parse);
    public static double[] RDoubles() => Array.ConvertAll(Console.ReadLine().Split(), double.Parse);
    public static int[] RInts(Func<string, int> func) => Console.ReadLine().Split().Select(func).ToArray();
    public static long[] RLongs(Func<string, long> func) => Console.ReadLine().Split().Select(func).ToArray();
    public static double[] RDoubles(Func<string, double> func) => Console.ReadLine().Split().Select(func).ToArray();
    //public static string[] RStrings(Func<string, string> func) => Console.ReadLine().Split().Select(func).ToArray();

    public static T1 ReadTuple<T1>()
    {
        var r = RString();
        var r1 = (T1)Convert.ChangeType(r, typeof(T1));
        return r1;
    }
    public static (T1, T2) ReadTuple<T1, T2>()
    {
        var r = RStrings();
        var r1 = (T1)Convert.ChangeType(r[0], typeof(T1));
        var r2 = (T2)Convert.ChangeType(r[1], typeof(T2));
        return (r1, r2);
    }
    public static (T1, T2, T3) ReadTuple<T1, T2, T3>()
    {
        var r = RStrings();
        var r1 = (T1)Convert.ChangeType(r[0], typeof(T1));
        var r2 = (T2)Convert.ChangeType(r[1], typeof(T2));
        var r3 = (T3)Convert.ChangeType(r[2], typeof(T3));
        return (r1, r2, r3);
    }
    public static (T1, T2, T3, T4) ReadTuple<T1, T2, T3, T4>()
    {
        var r = RStrings();
        var r1 = (T1)Convert.ChangeType(r[0], typeof(T1));
        var r2 = (T2)Convert.ChangeType(r[1], typeof(T2));
        var r3 = (T3)Convert.ChangeType(r[2], typeof(T3));
        var r4 = (T4)Convert.ChangeType(r[3], typeof(T4));
        return (r1, r2, r3, r4);
    }
}


Measured memory_bytes: 84376