#include <iostream>
#include <iomanip>
#include <cassert>
#include <vector>
#include <algorithm>
#include <utility>
#include <numeric>
#include <tuple>
#include <ranges>
namespace ranges = std::ranges;
namespace views = std::views;
// #include "Src/Number/IntegerDivision.hpp"
// #include "Src/Utility/BinarySearch.hpp"
// #include "Src/Sequence/CompressedSequence.hpp"
// #include "Src/Sequence/RunLengthEncoding.hpp"
// #include "Src/Algebra/Group/AdditiveGroup.hpp"
// #include "Src/DataStructure/FenwickTree/FenwickTree.hpp"
// #include "Src/DataStructure/SegmentTree/SegmentTree.hpp"
// #include "Src/DataStructure/DisjointSetUnion/DisjointSetUnion.hpp"
// using namespace zawa;
// #include "atcoder/modint"
// using mint = atcoder::modint998244353;
using namespace std;

int main() {
    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);
    int N;
    cin >> N;
    vector<int> A(N);
    for (auto& a : A) cin >> a;
    if (ranges::all_of(A, [&](int x) -> bool { return x == 0; })) cout << "No\n";
    else cout << "Yes\n";
}