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

using ll = long long;

int main()
{
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int N;
    cin >> N;
    bool zero = true;
    for (int i = 0; i < N; i++)
    {
        ll a;
        cin >> a;
        zero &= a == 0;
    }

    if (zero) cout << "No" << endl;
    else cout << "Yes" << endl;
}