#include <bits/stdc++.h>
using namespace std;
const double pi = 4 * atan(1);
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
int lcm(int a, int b) { return a / gcd(a, b) * b; }
const int LEN = 330;
int main() {
  long long x1, y1, x2, y2;
  long long n;
  long long arr[LEN][3];
  long long x, y;
  cin >> x1 >> y1;
  cin >> x2 >> y2;
  cin >> n;
  int ans = 0;
  for (int i = 0; i < n; i++) cin >> arr[i][0] >> arr[i][1] >> arr[i][2];
  for (int i = 0; i < n; i++) {
    x = arr[i][0] * x1 + arr[i][1] * y1 + arr[i][2];
    y = arr[i][0] * x2 + arr[i][1] * y2 + arr[i][2];
    if (x > 0 && y < 0 || x < 0 && y > 0) ans++;
  }
  cout << ans << endl;
  return 0;
}
