#include #include #include static inline constexpr const char* solve(const uint_fast32_t N, const std::vector& A) noexcept { uint_fast64_t deg_sum = 0; for (uint_fast32_t i = 1; i <= N; ++i) deg_sum += A[i] * i; if ((deg_sum & 1) != 0) return "No"; else if (deg_sum == A[1]) return "Yes"; uint_fast64_t leaf_count = 2; for (uint_fast32_t i = N; i != 1; --i) leaf_count += A[i] * (i - 2); if (leaf_count <= A[1]) return "Yes"; else return "No"; } int main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); uint_fast32_t N, i; std::cin >> N; std::vector A(N + 1); for (i = 0; i <= N; ++i) std::cin >> A[i]; std::cout << solve(N, A) << '\n'; return 0; }