#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  vector<pair<long long, long long> > segs;
  long long x1, x2, n, m, c;
  cin >> n;
  cin >> x1 >> x2;
  for (int i = 0; i < n; i++) {
    cin >> m >> c;
    segs.push_back(pair<long long, long long>(x1 * m + c, x2 * m + c));
  }
  sort(segs.begin(), segs.end());
  bool okay = false;
  int i = 0, j;
  long long maxiEnd = -(1LL << 61);
  while (i < segs.size()) {
    j = i;
    long long curMaxiEnd = -(1LL << 61);
    while (j < segs.size() && segs[i].first == segs[j].first) {
      long long s = segs[j].first;
      long long e = segs[j].second;
      if (e < maxiEnd) okay = true;
      curMaxiEnd = max(curMaxiEnd, e);
      j++;
    }
    maxiEnd = max(maxiEnd, curMaxiEnd);
    i = j;
  }
  cout << (okay ? "YES" : "NO") << endl;
  return 0;
}
