#include <bits/stdc++.h>
using namespace std;
const int N = 100100;
pair<long long, long long> re[N];
int main() {
  int n;
  scanf("%d", &n);
  long long x1, x2;
  scanf("%I64d%I64d", &x1, &x2);
  for (int i = 0; i < n; i++) {
    long long K, B;
    scanf("%I64d%I64d", &K, &B);
    re[i].first = K * x1 + B;
    re[i].second = K * x2 + B;
  }
  sort(re, re + n);
  set<long long> s;
  for (int i = 0, j = i; i < n; i = j) {
    long long mi = (1LL << 60);
    while (re[i].first == re[j].first) {
      mi = min(mi, re[j].second);
      j++;
    }
    if (s.upper_bound(mi) != s.end()) {
      puts("YES");
      return 0;
    }
    for (int k = i; k < j; k++) {
      s.insert(re[k].second);
    }
  }
  puts("NO");
  return 0;
}
