#include <bits/stdc++.h> #ifdef LOCAL #include <debug.hpp> #else #define debug(...) void(0) #endif template <class T> std::istream& operator>>(std::istream& is, std::vector<T>& v) { for (auto& e : v) { is >> e; } return is; } template <class T> std::ostream& operator<<(std::ostream& os, const std::vector<T>& v) { for (std::string_view sep = ""; const auto& e : v) { os << std::exchange(sep, " ") << e; } return os; } template <class T, class U = T> bool chmin(T& x, U&& y) { return y < x and (x = std::forward<U>(y), true); } template <class T, class U = T> bool chmax(T& x, U&& y) { return x < y and (x = std::forward<U>(y), true); } template <class T> void mkuni(std::vector<T>& v) { std::ranges::sort(v); auto result = std::ranges::unique(v); v.erase(result.begin(), result.end()); } template <class T> int lwb(const std::vector<T>& v, const T& x) { return std::distance(v.begin(), std::ranges::lower_bound(v, x)); } using ll = long long; using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); cout << fixed << setprecision(15); int N; cin >> N; vector<int> A(N); cin >> A; for (int& val : A) { if (val <= 1) { cout << "Yes\n"; return 0; } } cout << "No\n"; return 0; }