#include //ModInt template struct ModInt { private: int x; public: ModInt() : x(0) {} ModInt(long long x_) { if((x = x_ % mod + mod) >= mod) x -= mod; } int val() const { return x; } static int get_mod() { return mod; } constexpr ModInt& operator+=(ModInt rhs) { if((x += rhs.x) >= mod) x -= mod; return *this; } constexpr ModInt& operator-=(ModInt rhs) { if((x -= rhs.x) < 0) x += mod; return *this; } constexpr ModInt& operator*=(ModInt rhs) { x = (unsigned long long)x * rhs.x % mod; return *this; } constexpr ModInt& operator/=(ModInt rhs) { x = (unsigned long long)x * rhs.inv().x % mod; return *this; } constexpr ModInt operator-() const noexcept { return -x < 0 ? mod - x : -x; } constexpr ModInt operator+(ModInt rhs) const noexcept { return ModInt(*this) += rhs; } constexpr ModInt operator-(ModInt rhs) const noexcept { return ModInt(*this) -= rhs; } constexpr ModInt operator*(ModInt rhs) const noexcept { return ModInt(*this) *= rhs; } constexpr ModInt operator/(ModInt rhs) const noexcept { return ModInt(*this) /= rhs; } constexpr ModInt& operator++() { *this += 1; return *this; } constexpr ModInt operator++(int) { *this += 1; return *this - 1; } constexpr ModInt& operator--() { *this -= 1; return *this; } constexpr ModInt operator--(int) { *this -= 1; return *this + 1; } bool operator==(ModInt rhs) const { return x == rhs.x; } bool operator!=(ModInt rhs) const { return x != rhs.x; } bool operator<=(ModInt rhs) const { return x <= rhs.x; } bool operator>=(ModInt rhs) const { return x >= rhs.x; } bool operator<(ModInt rhs) const { return x < rhs.x; } bool operator>(ModInt rhs) const { return x > rhs.x; } ModInt inv() { int a = x, b = mod, u = 1, v = 0, t; while(b > 0) { t = a / b; std::swap(a -= t * b, b); std::swap(u -= t * v, v); } return ModInt(u); } ModInt pow(long long n) const { ModInt ret(1), mul(x); while(n > 0) { if(n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } ModInt sqrt() const { if(x <= 1) return x; int v = (mod - 1) / 2; if(pow(v) != 1) return -1; int q = mod - 1, m = 0; while(~q & 1) q >>= 1, m++; std::mt19937 mt; ModInt z = mt(); while(z.pow(v) != mod - 1) z = mt(); ModInt c = z.pow(q), t = pow(q), r = pow((q + 1) / 2); for(; m > 1; m--) { ModInt tmp = t.pow(1 << (m - 2)); if(tmp != 1) r = r * c, t = t * c * c; c = c * c; } return std::min(r.x, mod - r.x); } friend std::ostream& operator<<(std::ostream& s, ModInt a) { s << a.x; return s; } friend std::istream& operator>>(std::istream& s, ModInt& a) { s >> a.x; return s; } }; static int MOD = 998244353; using mint = ModInt; mint res, two = 2; int n, a; long long k; int main() { scanf("%d%lld", &n, &k); for(int i = 0; i < n; i++) { scanf("%d", &a); res += a; } res *= two.pow(k); std::cout << res << "\n"; }