#include //#include //#pragma GCC optimize("O3") using namespace std; #define reps(i,s,n) for(int i = s; i < n; i++) #define rep(i,n) reps(i,0,n) #define Rreps(i,n,e) for(int i = n - 1; i >= e; --i) #define Rrep(i,n) Rreps(i,n,0) #define ALL(a) a.begin(), a.end() using ll = long long; using vec = vector; using mat = vector; ll N,M,H,W,Q,K,A,B; string S; using P = pair; const ll INF = (1LL<<60); template bool chmin(T &a, const T &b){ if(a > b) {a = b; return true;} else return false; } template bool chmax(T &a, const T &b){ if(a < b) {a = b; return true;} else return false; } template void print_vector(std::vector v,bool endline = true){ if(!v.empty()){ for(std::size_t i{}; i class modint{ public: ll x; constexpr modint(){x = 0;} constexpr modint(ll _x) : x((_x < 0 ? ((_x += (LLONG_MAX / mod) * mod) < 0 ? _x + (LLONG_MAX / mod) * mod : _x) : _x)%mod){} constexpr modint set_raw(ll _x){ //_x in [0, mod) x = _x; return *this; } constexpr modint operator-(){ return x == 0 ? 0 : mod - x; } constexpr modint& operator+=(const modint& a){ if((x += a.x) >= mod) x -= mod; return *this; } constexpr modint operator+(const modint& a) const{ return modint(*this) += a; } constexpr modint& operator-=(const modint& a){ if((x -= a.x) < 0) x += mod; return *this; } constexpr modint operator-(const modint& a) const{ return modint(*this) -= a; } constexpr modint& operator*=(const modint& a){ (x *= a.x)%=mod; return *this; } constexpr modint operator*(const modint& a) const{ return modint(*this) *= a; } constexpr modint pow(unsigned long long pw) const{ modint res(1), comp(*this); while(pw){ if(pw&1) res *= comp; comp *= comp; pw >>= 1; } return res; } //以下、modが素数のときのみ constexpr modint inv() const{ if(x == 2) return (mod + 1) >> 1; return modint(*this).pow(mod - 2); } constexpr modint& operator/=(const modint &a){ (x *= a.inv().x)%=mod; return *this; } constexpr modint operator/(const modint &a) const{ return modint(*this) /= a; } }; #define mod1 998244353 using mint = modint; ostream& operator<<(ostream& os, const mint& a){ os << a.x; return os; } using vm = vector; const ll MAX_N = ll(4e+5) + 10; vm fact(MAX_N, mint(1)), fact_inv(MAX_N, mint(1)), n_inv(MAX_N, mint(1)), two_pow(MAX_N, mint(1)); void makefact(){ mint tmp; two_pow[1] = 2; reps(i,2,MAX_N) { fact[i] = fact[i-1] * tmp.set_raw(i); two_pow[i] = two_pow[i-1] * 2; } fact_inv[MAX_N - 1] = fact[MAX_N - 1].inv(); Rreps(i, MAX_N - 1, 1){ fact_inv[i] = fact_inv[i + 1] * tmp.set_raw(i + 1); n_inv[i + 1] = fact[i] * fact_inv[i + 1]; } } mint nCm(ll n, ll m){ return fact[n] * fact_inv[n-m] * fact_inv[m]; } mint nCm_inv(ll n, ll m){ return fact[n-m] * fact[m] * fact_inv[n]; } int main(){ makefact(); cin.tie(nullptr); ios::sync_with_stdio(false); cin>>N; mint res(0); rep(k, N){ int E = (N - 1 - k) - k + (k&1 ? -1 : 1); if(E<0) E = -E; res += nCm(N - 1, k) * 2 * two_pow[E]; } cout<