#include <bits/stdc++.h>
using namespace std;
 
#define fi first
#define se second
#define pb push_back
using vi = vector <int>;
using ll = long long;
using pii = pair <int, int>;
//~ const ll mod = 998244353;
const ll mod = 1e9 + 7;
ll qpow(ll a, ll b, ll m = mod) { ll r = 1, t = a;
	for(; b; b /= 2) { if(b & 1) r = r * t % m; t = t * t % m; } return r; }

int main() {
	ios :: sync_with_stdio(false);
	
	int p, q; cin >> p >> q;
	if(p == 0 && q == 0) {
		int ans = 0;
		int n; cin >> n;
		for(int i = 0; i < n; i ++) {
			int x, y; cin >> x >> y;
			if(x == 0 && y == 0)
				ans ++;
		}
		cout << ans << '\n';
	} else {
		int g = __gcd(p, q);
		p /= g; q /= g;
		
		int ans = 0;
		int n; cin >> n;
		for(int i = 0; i < n; i ++) {
			int x, y; cin >> x >> y;
			if(x % g == 0 && y % g == 0) {
				x /= g; y /= g;
				if((p + q) % 2 == 1)
					ans ++;
				else
					ans += ((x + y) % 2 == 0);
			}
		}
		
		cout << ans << '\n';
	}
}