#include <bits/stdc++.h>
#include <atcoder/all>
#include <boost/polygon/point_data.hpp>
#include <boost/polygon/voronoi.hpp>
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(x) begin(x),end(x)
#define sz(x) (int)(x).size()
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
using vll=vector<ll>;
using vvll=vector<vll>;
using pll=pair<ll,ll>;

// using mint=modint;

// using BoostPoint=boost::polygon::point_data<int>;
// using Voronoi=boost::polygon::voronoi_diagram<double>;

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

    ll P,Q,N;
    cin>>P>>Q>>N;

    if(P==0&&Q==0){
        ll ans=0;
        rep(i,0,N){
            ll X,Y;
            cin>>X>>Y;
            if(X==0&&Y==0)ans++;
        }
        cout<<ans<<'\n';
        return 0;
    }

    ll g=gcd(P,Q);
    ll p=P/g,q=Q/g;
    ll ans=0;
    
    if(p%2!=q%2){
        rep(i,0,N){
            ll X,Y;
            cin>>X>>Y;
            if(X%g||Y%g)continue;
            ans++;
        }
    }else{
        rep(i,0,N){
            ll X,Y;
            cin>>X>>Y;
            if(X%g||Y%g)continue;
            if((X/g-Y/g)%2==0)ans++;
        }
    }
    cout<<ans<<'\n';

}