#include <bits/stdc++.h>
using namespace std;
vector<pair<long long int, long long int> > v;
int main() {
  int n;
  scanf("%d", &n);
  long long int x1, x2;
  cin >> x1 >> x2;
  for (int i = 0; i < n; i++) {
    long long int l, r;
    long long int k, b;
    cin >> k >> b;
    l = x1 * k + b;
    r = x2 * k + b;
    v.push_back(make_pair(l, r));
  }
  sort(v.begin(), v.end());
  long long int y = v[0].second;
  for (int i = 1; i < n; i++) {
    if (v[i].first != v[i - 1].first) {
      if (v[i].second < y) {
        printf("YES\n");
        return 0;
      }
    } else {
    }
    y = v[i].second;
  }
  printf("NO\n");
  return 0;
}
