#include <bits/stdc++.h>
using namespace std;
long long n, a1, a2, b, k;
pair<long long, long long> a[200000];
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n;
  cin >> a1 >> a2;
  for (int i = 0; i < n; i++) {
    cin >> k >> b;
    a[i].first = k * a1 + b;
    a[i].second = k * a2 + b;
  }
  sort(a, a + n);
  for (int i = 0; i < n - 1; i++)
    if (a[i + 1].first > a[i].first && a[i].second > a[i + 1].second) {
      cout << "YES";
      return 0;
    }
  cout << "NO";
}
