#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  int n;
  cin >> n;
  long long int x1, x2, m, c, y1, y2;
  cin >> x1 >> x2;
  pair<long long int, long long int> a[n];
  for (int i = 0; i < n; i++) {
    cin >> m >> c;
    y1 = m * x1 + c;
    y2 = m * x2 + c;
    a[i] = {y1, y2};
  }
  sort(a, a + n);
  for (int i = 1; i < n; i++)
    if (a[i - 1].first < a[i].first && a[i - 1].second > a[i].second) {
      cout << "YES";
      return 0;
    }
  cout << "NO";
  return 0;
}
