#include <cstdio>
#include <cctype>
typedef long long ll;

namespace IO {
  const int BUFSIZE = 1 << 20;

  char buf[BUFSIZE], *p1, *p2;

  char gc() {
    if (p1 == p2) {
      p2 = (p1 = buf) + fread(buf, 1, BUFSIZE, stdin);
      if (p1 == p2) return EOF;
    }
    return *p1++;
  }

  template <typename T> T read() {
    T res = 0, f = 1;
    char ch = gc();
    for (; !isdigit(ch); ch = gc()) if (ch == '-') f = -1;
    for (; isdigit(ch); ch = gc()) res = (res << 3) + (res << 1) + (ch ^ 48);
    return res * f;
  }

  template <typename T> void write(T x, char ed = '\n') {
    if (x < 0) x = -x, putchar('-');
    static int sta[sizeof(T) << 2], top = 0;
    do {
      sta[++top] = x % 10;
      x /= 10;
    } while (x);
    while (top) {
      putchar(sta[top--] ^ 48);
    }
    putchar(ed);
  }
};

#include <vector>
const int MAXN = 5e5 + 10;

struct Vector {
  ll x, y, c;
} v[MAXN], target;

int n;

namespace Sub1 {
  int Work() {
    IO::write(target.x * v[2].c + target.y * v[1].c);
    return 0;
  }
};

int main() {
  #ifdef LOCAL
    freopen("!input.in", "r", stdin);
    freopen("!output.out", "w", stdout);
  #else
    freopen("tioj_constructive.in", "r", stdin);
    freopen("tioj_constructive.out", "w", stdout);
  #endif

  n = IO::read<int>(), target.x = IO::read<ll>(), target.y = IO::read<ll>();
  for (int i = 1; i <= n; ++i) {
    v[i].x = IO::read<ll>(), v[i].y = IO::read<ll>(), v[i].c = IO::read<ll>();
  }

  if (n == 2 && v[1].x == 0 && v[1].y == 1 && v[2].x == 1 && v[2].y == 0) return Sub1::Work();
  IO::write(-1);
  return 0;
}