#include <bits/stdc++.h>   using namespace std;   int n;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cin >> n;     int sl = 0;     for (int i = 1; i <= n; ++i) {       int x, y;       cin >> x >> y;       if (x > 0) ++sl;     }     if (sl == n || sl == 0 || sl == n - 1 || sl == 1) {       cout <<  Yes ;       return 0;     }     cout <<  No ;   }   