#include <bits/stdc++.h>
using namespace std;
const int maxn = 100000 + 10;
int n;
long long L, R, opk, opb, maxt = -1000000000000000ll;
long long x[maxn], y[maxn];
int ra[maxn];
double fl;
bool cmp(int A, int B) {
  if (x[A] == x[B]) return y[A] < y[B];
  return x[A] < x[B];
}
int main() {
  scanf("%d", &n);
  scanf("%I64d%I64d", &L, &R);
  for (int i = 0; i < n; i++) {
    scanf("%I64d%I64d", &opk, &opb);
    x[i] = opk * L + opb;
    y[i] = opk * R + opb;
  }
  for (int i = 0; i < n; i++) ra[i] = i;
  sort(ra, ra + n, cmp);
  for (int i = 0; i < n; i++) {
    int t = ra[i];
    if (i && x[t] == x[ra[i - 1]] && y[t] == y[ra[i - 1]]) fl = true;
    if (y[t] < maxt) fl = true;
    maxt = max(maxt, y[t]);
    if (fl) break;
  }
  if (fl)
    puts("YES");
  else
    puts("NO");
  return 0;
}
