#include "bits/stdc++.h"
#include "ext/pb_ds/assoc_container.hpp"
#include "ext/pb_ds/tree_policy.hpp"
#define ordered_set tree<pair<int, int>, null_type, less<pair<int, int>>, rb_tree_tag, tree_order_statistics_node_update>
using namespace std;
using namespace __gnu_pbds;
#define int long long int
#define pb push_back
#define vec vector<int>
#define fo(i, n) for (int i = 0; i < n; i++)
#define foo(i, a, b) for (int i = a; i < b; i++)
#define mp make_pair
#define deb(x) cout << #x << " --> " << x << endl;
#define deb1a(v)                  \
    cout << #v << "--->" << endl; \
    for (auto it : v)             \
        cout << it << " ";        \
    cout << endl;
#define deb2a(v)                  \
    cout << #v << "--->" << endl; \
    for (auto it : v)             \
    {                             \
        for (auto it1 : it)       \
        {                         \
            cout << it1 << " ";   \
        }                         \
        cout << endl;             \
    }
#define deb3a(v)                               \
    cout << #v << "-->" << endl;               \
    for (auto it : v)                          \
    {                                          \
        cout << it.fi << " " << it.se << endl; \
    }
#define mod 1000000007
#define so(v) sort(v.begin(), v.end())
#define fi first
#define se second
#define db1(x) cout << #x << "=" << x << endl
#define db2(x, y) cout << #x << "=" << x << "," << #y << "=" << y << endl
#define db3(x, y, z) cout << #x << "=" << x << "," << #y << "=" << y << "," << #z << "=" << z << endl
int power(int x, unsigned int y, int p)
{
    int res = 1;
    x = x % p;
    while (y > 0)
    {
        if (y & 1)
            res = (res * x) % p;
        y = y >> 1;
        x = (x * x) % p;
    }
    return res;
}
int mI(int a, int m)
{
    return power(a, m - 2, m);
}
vector<vector<int>> dir = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};

void solve()
{
    int n, m;
    cin >> n >> m;
    int x;
    cin >> x;
    vector<pair<int, int>> v(x);
    map<int, int> mm;
    fo(i, x)
    {
        cin >> v[i].fi >> v[i].se;
        mm[v[i].se]++;
    }
    multiset<int> s;
    for (auto it : mm)
    {

        s.insert(it.se);
    }
    so(v);
    int i = 0;
    int j = 0;
    int ans = 0;
    while (i < x)
    {
        //deb(i);
        while (j<x&&v[j].fi == v[i].fi )
        {
            //deb(j);
            s.erase(s.find(mm[v[j].se]));
            mm[v[j].se]--;
            if (mm[v[j].se])
                s.insert(mm[v[j].se]);
            j++;
        }
        //deb(x);
        auto it = s.end();

        int ans1 = 0;
        if (s.size() == 0)
            ans1 = 0;
        else
        {
            it--;
            ans1 = *it;
        }
        ans1 += j - i;
        foo(ii, i, j) {
            //deb(ii);
            if(mm[v[ii].se])
            s.erase(s.find(mm[v[ii].se]));
            mm[v[ii].se]++;
            s.insert(mm[v[ii].se]);
            
        }
        i = j;
        ans = max(ans, ans1);
    }
    cout << ans;
}
int32_t main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    srand(time(0));

    // FILE *fin = freopen("ip.txt","r",stdin);
    // FILE *fout = freopen("op.txt","w",stdout);
    int t = 1, nn = 1;
    //cin >> t;
    while (t--)
    {
        // cout << "Case #" << nn << ":"
        //      << " ";
        // nn++;
        solve();
    }
}

Measured memory_bytes: 40680