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

tuple<int, int, int> ext_gcd(int a, int b) {
  if (!b) return {1, 0, a};
  int x, y, g;
  tie(x, y, g) = ext_gcd(b, a % b);
  return {y, x - a / b * y, g};
}

signed main() {
  ios::sync_with_stdio(false);

  int A, B, C, D;
  cin >> A >> B >> C >> D;
  if (C < A) swap(A, C), swap(B, D);

  int N;
  cin >> N;

  map<pair<long long, long long>, int> gcnt;
  int gx, xx, yy; tie(xx, yy, gx) = ext_gcd(A, C);
  int gy = __gcd(B, D);
  if (!gx || !gy) {
    for (int i = 0; i < N; ++i) {
      long long x, y;
      cin >> x >> y;
      if (gx) {
        x %= gx;
        if (x < 0) x += gx;
      }
      if (gy) {
        y %= gy;
        if (y < 0) y += gy;
      }
      ++gcnt[make_pair(x, y)];
    }
  } else {
    for (int i = 0; i < N; ++i) {
      long long x, y;
      cin >> x >> y;
      if (gx <= x) {
        long long k = (x - 1) / gx;
        x -= k * gx;
        y -= 1LL * k * (1LL * xx * B + 1LL * yy * D);
      }
      long long zero = 1LL * A / gx * D - 1LL * C / gx * B;
      if (zero) {
        if (zero < 0) zero *= -1;
        y %= zero;
        if (y < 0) y += zero;
      }
      ++gcnt[make_pair(x, y)];
    }
  }

  cout << gcnt.size() << endl;

  return 0;
}