#include <bits/stdc++.h>
using namespace std;
int main() {
  int n = 0;
  cin >> n;
  long long a = 0, b = 0;
  cin >> a;
  cin >> b;
  vector<pair<int, int>> lines(n);
  for (int i = 0; i < n; i++) {
    cin >> lines[i].first;
    cin >> lines[i].second;
  }
  vector<pair<double, double>> dots(n);
  for (int i = 0; i < n; i++) {
    dots[i].first = lines[i].first * a + lines[i].second;
    dots[i].second = lines[i].first * b + lines[i].second;
  }
  sort(dots.begin(), dots.end());
  for (int i = 0; i < n - 1; i++) {
    if (dots[i].second > dots[i + 1].second) {
      cout << "YES";
      return 0;
    }
  }
  cout << "NO";
  return 0;
}
