import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayDeque;
import java.util.HashMap;
import java.util.Queue;
 
public class Main {
	public static void main(String[] args) throws NumberFormatException,
	IOException {Solve solve = new Solve();solve.solve();}
}
class Solve{
	class Pos{
		int x, y;
		Pos(int x, int y){
			this.x = x;
			this.y = y;
		}
	}
	void solve() throws NumberFormatException, IOException{
		ContestScanner in = new ContestScanner();
		Writer out = new Writer();
		
//		int a = in.nextInt();
//		int b = in.nextInt();
//		int[] dx = {a, a, b, b, -a, -a, -b, -b};
//		int[] dy = {b, -b, a, -a, a, -a, b, -b};
//		int h = 41;
//		int w = 41;
//		boolean[][] map = new boolean[41][41];
//		Queue<Pos> qu = new ArrayDeque<>();
//		qu.add(new Pos(20, 20));
//		while(!qu.isEmpty()){
//			Pos p = qu.poll();
//			if(map[p.y][p.x]) continue;
//			map[p.y][p.x] = true;
//			for(int i=0; i<dx.length; i++){
//				final int nx = dx[i]+p.x;
//				final int ny = dy[i]+p.y;
//				if(nx<0||nx>=41||ny<0||ny>=41) continue;
//				qu.add(new Pos(nx, ny));
//			}
//		}
//		for(int i=0; i<h; i++){
//			for(int j=0; j<w; j++){
//				System.out.print(map[i][j]?'o':'x');
//			}
//			System.out.println();
//		}
		int p = in.nextInt();
		int q = in.nextInt();
		int g;
		if(p==0&&q==0){
			int n = in.nextInt();
			int count = 0;
			for(int i=0; i<n; i++){
				int x = in.nextInt();
				int y = in.nextInt();
				if(x==0&&y==0)count++;
			}
			System.out.println(count);
			return;
		}
		if(p==0||q==0){
			g = p+q;
		}else g = gcd(p, q);
		int diff = Math.max(p, q)/g-Math.min(p, q)/g;
		int n = in.nextInt();
		int count = 0;
		for(int i=0; i<n; i++){
			int x = in.nextInt();
			int y = in.nextInt();
			if(x%g==0&&y%g==0){
				x /= g;
				y /= g;
				if(diff%2!=0||(x+y)%2==0){
					count++;
					continue;
				}
			}
		}
//		int g;
//		if(a==0||b==0){
//			g = a+b;
//		}else g = gcd(a, b);
//		int diff = Math.max(a, b)/g-Math.min(a, b)/g;
//		for(int i=0; i<h; i++){
//			for(int j=0; j<w; j++){
//				int y = i-20;
//				int x = j-20;
//				if(x%g==0&&y%g==0){
//					if(diff%2!=0||(x+y)%2==0)
//					System.out.print('o');
//					else System.out.print('x');
//				}else System.out.print('x');
//			}
//			System.out.println();
//		}
		System.out.println(count);
	}
	static int gcd(int a, int b){
		return b == 0 ? a : gcd(b, a % b);
	}
	
}

class MultiSet<T> extends HashMap<T, Integer>{
	@Override
	public Integer get(Object key){return containsKey(key)?super.get(key):0;}
	public void add(T key,int v){put(key,get(key)+v);}
	public void add(T key){put(key,get(key)+1);}
	public void sub(T key){
		final int num = get(key);
		if(num==1) remove(key);
		else put(key, num-1);
	}
}
class Timer{
	long time;
	public void set(){time = System.currentTimeMillis();}
	public long stop(){return System.currentTimeMillis()-time;}
}
class Writer extends PrintWriter{
	public Writer(String filename) throws IOException
	{super(new BufferedWriter(new FileWriter(filename)));}
	public Writer() throws IOException{super(System.out);}
}
class ContestScanner {
	private BufferedReader reader;
	private String[] line;
	private int idx;
	public ContestScanner() throws FileNotFoundException 
	{reader = new BufferedReader(new InputStreamReader(System.in));}
	public ContestScanner(String filename) throws FileNotFoundException
	{reader = new BufferedReader(new InputStreamReader(new FileInputStream(filename)));}
	public String nextToken() throws IOException {
		if (line == null || line.length <= idx) {
			line = reader.readLine().trim().split(" ");
			idx = 0;
		}
		return line[idx++];
	}
	public String readLine() throws IOException{return reader.readLine();}
	public long nextLong() throws IOException, NumberFormatException
	{return Long.parseLong(nextToken());}
	public int nextInt() throws NumberFormatException, IOException
	{return (int) nextLong();}
	public double nextDouble() throws NumberFormatException, IOException 
	{return Double.parseDouble(nextToken());}
}