#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 1e9 + 7;
const int N = 200005;
const int INF = 0x3f3f3f3f;

int main() {
    int n;
    cin >> n;
    ll sum = 0;
    for (int i = 0; i < n; i++) {
        ll x;
        cin >> x;
        sum += x;
    }
    if (sum > 0) {
        cout << "Yes\n";
    } else {
        cout << "No\n";
    }
    return 0;
}