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

#define InTheNameOfGod cin.tie(0); ios::sync_with_stdio(0);

typedef pair<int, int> pii;

int main()
{
    InTheNameOfGod

    int sor, pont;
    cin >> sor >> pont >> pont;
    pii pontok[pont];
    int indulok[pont];
    //read all the coordinations at once
    for(auto &it : pontok)
        cin >> it.first >> it.second;
    sort(pontok, pontok+pont);

    int lis_len = 0;
    for(auto akt : pontok) {
        int idx = lower_bound(indulok, indulok + lis_len, -akt.second) - indulok;
        indulok[idx] = -akt.second;
        if(idx == lis_len)
            lis_len++;
    }
    cout << lis_len;
}