#include<bits/stdc++.h>
/*
#include<atcoder/all>
using namespace atcoder;
using mint = modint1000000007;
*/
//g++ -I/opt/ac-library ./**.cpp
using namespace std;
using ll = long long;
using ull = unsigned long long;
const long long MOD = 1000000007;
const long double PI = 3.14159265358979;
const long long INF = 1LL<<60;
template <typename T> bool chmax(T &a, const T& b){if(a < b){a = b;return true;}return false;}
template <typename T> bool chmin(T &a, const T& b){if(a > b){a = b;return true;}return false;}
ll gcd(ll a, ll b){if (b == 0) return a;else return gcd(b, a % b);}
ll lcm(ll x,ll y){return ll(x/gcd(x,y))*y;}
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
#define int long long

int32_t main() {
    int n; cin >> n;
    int m; cin >> m;
    int q; cin >> q;

    vector<pair<int,int>> AB(q), IAB(q);

    for(int i=0; i<q; i++) {
        int a, b; cin >> a >> b;
        AB[i] = {a, b};
        IAB[i] = {a, -b};
    }

    sort(AB.begin(), AB.end());
    sort(IAB.begin(), IAB.end());

    vector<int> B(q);
    int cnt = 0;
    for(int i=0; i<q; i++) {
        B[i] = -IAB[i].second;
    }

    vector<int> LIS(B.size(), INF);
    for(int i=0; i<B.size(); i++) {
        int id = lower_bound(LIS.begin(), LIS.end(), B[i]) - LIS.begin();
        LIS[id] = B[i];
    }
    int res = lower_bound(LIS.begin(), LIS.end(), INF) - LIS.begin();
    cout << res << endl;
//for(int i=0; i<m; i++) cout << LIS[i] <<" ";cout << endl;
}