#include<bits/stdc++.h>
using namespace std;
using Int = long long;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}


//INSERT ABOVE HERE
signed main(){
  int a,b,c,d;
  cin>>a>>b>>c>>d;
  int n;
  cin>>n;
  vector<int> xs(n),ys(n);
  for(int i=0;i<n;i++) cin>>xs[i]>>ys[i];

  int gx=__gcd(a,c);
  int gy=__gcd(b,d);

  using P = pair<int, int>;
  set<P> sp;
  for(int i=0;i<n;i++)
    sp.emplace(gx?xs[i]%gx:xs[i],gy?ys[i]%gy:ys[i]);

  cout<<sp.size()<<endl;
  return 0;
}