#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
  int n; cin >> n;
  vector<int> a(n);
  ll s = 0;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    s += a[i];
  }
  sort(a.begin(), a.end());
  if (s >= 0 and s - a.back() <= 0) cout << "Yes" << endl;
  else if (s <= 0 and s - a.front() >= 0) cout << "Yes" << endl;
  else cout << "No" << endl;
}