#include <bits/stdc++.h>
#include <cmath>
#include <climits>
#include <cstdio>

using namespace std;

#define endl '\n'
#define PB push_back
#define ALL(a)  (a).begin(),(a).end()
#define SZ(a) int((a).size())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n)  FOR(i,0,n)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define AALL(a,n) (a),(a)+(n)

typedef pair<int,int> P;
typedef long long int LL;
typedef unsigned long long ULL;
typedef pair<LL,LL> LP;

#define int LL

pair<long long, long long> extgcd(long long a,long long b)
{
	if(b==1){
		return pair<long long, long long>(0,1);
	}
	pair<long long, long long> t=extgcd(b,a%b);
	return pair<long long, long long>(t.second,t.first-a/b*t.second);
}

long long gcd(long long x, long long y){
	return y==0 ? x : gcd(y, x%y);
}

signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	LL p,q;
	int n;
	cin >> p >> q;
	cin >> n;
	vector<int> x(n),y(n);
	REP(i,n)	cin >> x[i] >> y[i];
	int ans = 0;
	if(p != 0 && q != 0){
		LL g = gcd(p,q);
		P tmp = extgcd(p/g,q/g);
		p /= g; q /= g;
		int k = tmp.first, l = tmp.second;
		REP(i,n){
			if(x[i]%g == 0 && y[i]%g == 0){
				x[i] /= g;
				y[i] /= g;
				//DEBUG(x[i]); DEBUG(y[i]); DEBUG(k); DEBUG(l);
				bool f1 = false, f2 = false;
				REP(a,2){
					REP(b,2){
						//DEBUG(k*p+l*q);
						/*if((((q*b+k*y[i])+(l*x[i]-p*a))%2+2)%2 == 0 && (((l*y[i]-p*a)+(q*b+k*x[i]))%2+2)%2 == 0){
							//DEBUG(i);
							f1 = true;
						}*/
						if(((k*x[i]-q*a+p*b+l*y[i])%2+2)%2 == 0 && ((p*a+l*x[i]+k*y[i]-q*b)%2+2)%2 == 0){
							f1 = true;
						}
					}
				}
				/*REP(a,2){
					REP(b,2){
						if((((l*y[i]-p*a)+(q*b+k*x[i]))%2+2)%2 == 0){
							//DEBUG(i);
							f2 = true;
						}
					}
				}*/
				if(f1){
					//DEBUG(i);
					ans++;
				}
			}
		}
	}else if(p == 0 && q == 0){
		REP(i,n){
			if(x[i] == 0 && y[i] == 0){
				ans++;
			}
		}
	}else{
		int num = p^q;
		REP(i,n){
			if(x[i]%num == 0 && y[i]%num == 0){
				ans++;
			}
		}
	}
	cout << ans << endl;
	return 0;
}