#include <bits/stdc++.h>
using namespace std;
template <class T>
inline T bigmod(T p, T e, T M) {
  long long ret = 1;
  for (; e > 0; e >>= 1) {
    if (e & 1) ret = (ret * p) % M;
    p = (p * p) % M;
  }
  return (T)ret;
}
template <class T>
inline T gcd(T a, T b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
template <class T>
inline T modinverse(T a, T M) {
  return bigmod(a, M - 2, M);
}
template <class T>
inline T lcm(T a, T b) {
  a = abs(a);
  b = abs(b);
  return (a / _gcd(a, b)) * b;
}
template <class T, class X>
inline bool getbit(T a, X i) {
  T t = 1;
  return ((a & (t << i)) > 0);
}
template <class T, class X>
inline T setbit(T a, X i) {
  T t = 1;
  return (a | (t << i));
}
template <class T, class X>
inline T resetbit(T a, X i) {
  T t = 1;
  return (a & (~(t << i)));
}
inline long long power(long long a, long long b) {
  long long multiply = 1;
  for (int i = (0); i < (b); i++) {
    multiply *= a;
  }
  return multiply;
}
long long a[400], b[400], c[400];
int n;
int main() {
  ios_base::sync_with_stdio(0);
  long long x1, x2, y1, y2;
  cin >> x1 >> y1 >> x2 >> y2;
  cin >> n;
  for (int i = (0); i < (n); i++) {
    cin >> a[i] >> b[i] >> c[i];
  }
  int cnt = 0;
  for (int i = (0); i < (n); i++) {
    long long r1 = a[i] * x1 + b[i] * y1 + c[i];
    long long r2 = a[i] * x2 + b[i] * y2 + c[i];
    if (r1 < 0 && r2 > 0)
      cnt++;
    else if (r1 > 0 && r2 < 0)
      cnt++;
  }
  cout << cnt << endl;
  return 0;
}
