#include<bits/stdc++.h>
//#include<atcoder/all>
using namespace std;
//using namespace atcoder;

#define repr(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) repr(i, 0, n)
#define INF 2e9
//#define MOD 1000000007
#define MOD 998244353
#define LINF (long long)4e18
#define jck 3.141592
#define PI acos(-1.0)

const double EPS = 1e-15;

using ll = long long;
using Pi = pair<int,int>;
using Pl = pair<ll,ll>;
//using mint = modint998244353;

int dh[] = {-1,0,1,0};
int dw[] = {0,1,0,-1};


int main(){
    int n,m,q; cin >> n >> m >> q;
    vector<Pi> ab(q);
    rep(i,q){
        cin >> ab[i].first >> ab[i].second;
    }
    sort(ab.begin(),ab.end());
    vector<int> c(q);
    rep(i,q) c[i] = ab[i].second;
    vector<int> dp(q,INF);
    rep(i,q){
        *lower_bound(dp.begin(),dp.end(),c[i]) = c[i];
    }
    cout << lower_bound(dp.begin(),dp.end(),INF)-dp.begin() <<endl;
}