#include <bits/stdc++.h>
using namespace std;
int n;
long long int xa, xb, k, b;
pair<long long int, long long int> y[100005];
int main() {
  scanf("%d", &n);
  scanf("%lld %lld", &xa, &xb);
  for (int i = 0; i < n; i++) {
    scanf("%lld %lld", &k, &b);
    y[i].first = k * xa + b;
    y[i].second = k * xb + b;
  }
  sort(y, y + n);
  long long int last = y[0].second;
  for (int i = 1; i < n; i++) {
    if (y[i].second < last) {
      cout << "YES" << endl;
      return 0;
    } else {
      last = y[i].second;
    }
  }
  cout << "NO" << endl;
}
