#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
constexpr int INF = 1001001001;
// constexpr int mod = 1000000007;
constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

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

    int P, Q, N, X, Y;
    cin >> P >> Q >> N;
    int G = gcd(P, Q);
    if(G != 0)  P /= G, Q /= G;
    int ans = 0;
    for(int i = 0; i < N; ++i){
        cin >> X >> Y;
        if(G == 0){
            ans += (X == 0 && Y == 0);
            continue;
        }
        if(X % G != 0 || Y % G != 0)    continue;
        X /= G, Y /= G;
        if((P % 2) ^ (Q % 2)){
            ans += 1;
        }
        else{
            ans += (X + Y) % 2 == 0;
        }
    }
    cout << ans << endl;

    return 0;
}