#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
using namespace std;
int x[100005],y[100005],q[100005],w[100005];
int find(){
	
}
int main(){
	freopen("asm_second.in","r",stdin);
	freopen("asm_second.out","w",stdout);
	int n,a,b,c,d,num=0;
	cin>>n;
	cin>>a>>b>>c>>d;
	if(a==0&&b==1&&c==1&&d==0){
		cout<<n;
		return 0;
	}
	for(int i=1;i<=n;i++){
		cin>>x[i]>>y[i];
		if(y[i]*b<=a*x[i]||y[i]*d>=x[i]*c||x[i]==0||y[i]==0){
			n--;
			i--;
		}else{
			q[i]=x[i];
			w[i]=y[i];
		}
	}
	find();
	return 0;
}