#include <bits/stdc++.h>
using namespace std;

long long to (double x)
{
    return round (x * 1000.0);
}
int main()
{
	int num = 0;
    double a1,b1,a2,b2,x,y;
    int n;
    cin >> a1 >> b1 >> a2 >> b2;
    cin >> n;
    a1 = to(a1);
    b1 = to(b1);
    a2 = to(a2);
    b2 = to(b2);

    while (n--)
    {
    	
    	bool xian = 0;
		bool mian = 0;
        cin >> x >> y;
        x = to(x),y = to(y);
        
        if (x >= min(a1,a2)&&y >= min(b1,b2)&& x <= max(a1,a2)&&y <= max(b1,b2)) mian = 1;
        
        if ( (b2-b1) * (x-a1)== (a2-a1) * (y-b1) )xian = 1;
        
        if (xian == 1 && mian == 1)
        {
        	num ++;
		}
    }
    	cout << num << "\n";
}