#include <bits/stdc++.h>
using namespace std;
const int INF = 10000;
int main(){
  int N, M, Q;
  cin >> N >> M >> Q;
  vector<int> a(Q), b(Q);
  for (int i = 0; i < Q; i++){
    cin >> a[i] >> b[i];
    a[i]--;
    b[i]--;
  }
  vector<vector<int>> b2(N);
  for (int i = 0; i < Q; i++){
    b2[a[i]].push_back(b[i]);
  }
  for (int i = 0; i < N; i++){
    sort(b2[i].begin(), b2[i].end(), greater<int>());
  }
  vector<int> x;
  for (int i = 0; i < N; i++){
    int cnt = b2[i].size();
    for (int j = 0; j < cnt; j++){
      x.push_back(b2[i][j]);
    }
  }
  vector<int> dp(Q, INF);
  for (int i = 0; i < Q; i++){
    *lower_bound(dp.begin(), dp.end(), x[i]) = x[i];
  }
  cout << lower_bound(dp.begin(), dp.end(), INF) - dp.begin() << endl;
}