#line 1 "a.cpp" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* macro */ #define rep(i, a, n) for (int i = (int)(a); i < (int)(n); i++) #define rrep(i, a, n) for (int i = ((int)(n)-1); i >= (int)(a); i--) #define Rep(i, a, n) for (i64 i = (i64)(a); i < (i64)(n); i++) #define RRep(i, a, n) for (i64 i = ((i64)(n)-i64(1)); i >= (i64)(a); i--) #define all(v) (v).begin(), (v).end() #define rall(v) (v).rbegin(), (v).rend() /* macro end */ /* template */ namespace ebi { #ifdef LOCAL #define debug(...) \ std::cerr << "LINE: " << __LINE__ << " [" << #__VA_ARGS__ << "]:", \ debug_out(__VA_ARGS__) #else #define debug(...) #endif void debug_out() { std::cerr << std::endl; } template void debug_out(Head h, Tail... t) { std::cerr << " " << h; if (sizeof...(t) > 0) std::cerr << " :"; debug_out(t...); } template std::ostream &operator<<(std::ostream &os, const std::pair &pa) { return os << pa.first << " " << pa.second; } template std::istream &operator>>(std::istream &os, std::pair &pa) { return os >> pa.first >> pa.second; } template std::ostream &operator<<(std::ostream &os, const std::vector &vec) { for (std::size_t i = 0; i < vec.size(); i++) os << vec[i] << (i + 1 == vec.size() ? "" : " "); return os; } template std::istream &operator>>(std::istream &os, std::vector &vec) { for (T &e : vec) std::cin >> e; return os; } template std::ostream &operator<<(std::ostream &os, const std::optional &opt) { if (opt) { os << opt.value(); } else { os << "invalid value"; } return os; } using std::size_t; using i32 = std::int32_t; using u32 = std::uint32_t; using i64 = std::int64_t; using u64 = std::uint64_t; using i128 = __int128_t; using u128 = __uint128_t; template inline bool chmin(T &a, T b) { if (a > b) { a = b; return true; } return false; } template inline bool chmax(T &a, T b) { if (a < b) { a = b; return true; } return false; } template T pow(T x, i64 n) { T res = 1; while (n > 0) { if (n & 1) res = res * x; x = x * x; n >>= 1; } return res; } template struct Edge { int to; T cost; Edge(int _to, T _cost = 1) : to(_to), cost(_cost) {} }; template struct Graph : std::vector>> { using std::vector>>::vector; void add_edge(int u, int v, T w, bool directed = false) { (*this)[u].emplace_back(v, w); if (directed) return; (*this)[v].emplace_back(u, w); } }; struct graph : std::vector> { using std::vector>::vector; void add_edge(int u, int v, bool directed = false) { (*this)[u].emplace_back(v); if (directed) return; (*this)[v].emplace_back(u); } }; constexpr i64 LNF = std::numeric_limits::max() / 4; constexpr int INF = std::numeric_limits::max() / 2; const std::vector dy = {1, 0, -1, 0, 1, 1, -1, -1}; const std::vector dx = {0, 1, 0, -1, 1, -1, 1, -1}; } // namespace ebi #line 2 "convolution/ntt.hpp" #line 4 "convolution/ntt.hpp" #include #line 8 "convolution/ntt.hpp" #line 2 "math/internal_math.hpp" #line 4 "math/internal_math.hpp" namespace ebi { namespace internal { constexpr int primitive_root_constexpr(int m) { if (m == 2) return 1; if (m == 167772161) return 3; if (m == 469762049) return 3; if (m == 754974721) return 11; if (m == 998244353) return 3; if (m == 880803841) return 26; assert(0); return -1; } template constexpr int primitive_root = primitive_root_constexpr(m); } // namespace internal } // namespace ebi #line 2 "utility/bit_operator.hpp" namespace ebi { constexpr int bsf_constexpr(unsigned int n) { int x = 0; while (!(n & (1 << x))) x++; return x; } int bit_reverse(int n, int bit_size) { int rev_n = 0; for (int i = 0; i < bit_size; i++) { rev_n |= ((n >> i) & 1) << (bit_size - i - 1); } return rev_n; } int ceil_pow2(int n) { int x = 0; while ((1U << x) < (unsigned int)(n)) x++; return x; } int popcnt(int x) { return __builtin_popcount(x); } int msb(int x) { return (x == 0) ? -1 : 31 - __builtin_clz(x); } int bsf(int x) { return (x == 0) ? -1 : __builtin_ctz(x); } } // namespace ebi #line 2 "utility/modint_base.hpp" #line 4 "utility/modint_base.hpp" namespace ebi { namespace internal { struct modint_base {}; template using is_modint = std::is_base_of; template using is_modint_t = std::enable_if_t::value>; struct static_modint_base : modint_base {}; template using is_static_modint = std::is_base_of; template using is_static_modint_t = std::enable_if_t::value>; } // namespace internal } // namespace ebi #line 12 "convolution/ntt.hpp" namespace ebi { namespace internal { template , internal::is_static_modint_t* = nullptr> struct ntt_info { static constexpr int rank2 = bsf_constexpr(mint::mod() - 1); std::array root, inv_root; ntt_info() { root[rank2] = mint(g).pow((mint::mod() - 1) >> rank2); inv_root[rank2] = root[rank2].inv(); for (int i = rank2 - 1; i >= 0; i--) { root[i] = root[i + 1] * root[i + 1]; inv_root[i] = inv_root[i + 1] * inv_root[i + 1]; } } }; template * = nullptr> void butterfly(std::vector& a) { static const ntt_info info; int n = int(a.size()); int bit_size = bsf(n); assert(n == 1 << ceil_pow2(n)); // bit reverse for (int i = 0; i < n; i++) { int rev = bit_reverse(i, bit_size); if (i < rev) { std::swap(a[i], a[rev]); } } for (int bit = 0; bit < bit_size; bit++) { for (int i = 0; i < n / (1 << (bit + 1)); i++) { mint zeta1 = 1; mint zeta2 = info.root[1]; for (int j = 0; j < (1 << bit); j++) { int idx = i * (1 << (bit + 1)) + j; int jdx = idx + (1 << bit); mint p1 = a[idx]; mint p2 = a[jdx]; a[idx] = p1 + zeta1 * p2; a[jdx] = p1 + zeta2 * p2; zeta1 *= info.root[bit + 1]; zeta2 *= info.root[bit + 1]; } } } } template * = nullptr> void butterfly_inv(std::vector& a) { static const ntt_info info; int n = int(a.size()); int bit_size = bsf(n); assert(n == 1 << ceil_pow2(n)); // bit reverse for (int i = 0; i < n; i++) { int rev = bit_reverse(i, bit_size); if (i < rev) std::swap(a[i], a[rev]); } for (int bit = 0; bit < bit_size; bit++) { for (int i = 0; i < n / (1 << (bit + 1)); i++) { mint zeta1 = 1; mint zeta2 = info.inv_root[1]; for (int j = 0; j < (1 << bit); j++) { int idx = i * (1 << (bit + 1)) + j; int jdx = idx + (1 << bit); mint p1 = a[idx]; mint p2 = a[jdx]; a[idx] = p1 + zeta1 * p2; a[jdx] = p1 + zeta2 * p2; zeta1 *= info.inv_root[bit + 1]; zeta2 *= info.inv_root[bit + 1]; } } } mint inv_n = mint(n).inv(); for (int i = 0; i < n; i++) { a[i] *= inv_n; } } } // namespace internal template * = nullptr> std::vector convolution_naive(const std::vector& f, const std::vector& g) { if (f.empty() || g.empty()) return {}; int n = int(f.size()), m = int(g.size()); std::vector c(n + m - 1); if (n < m) { for (int j = 0; j < m; j++) { for (int i = 0; i < n; i++) { c[i + j] += f[i] * g[j]; } } } else { for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { c[i + j] += f[i] * g[j]; } } } return c; } template * = nullptr> std::vector convolution(const std::vector& f, const std::vector& g) { if (f.empty() || g.empty()) return {}; if (std::min(f.size(), g.size()) < 60) return convolution_naive(f, g); int n = 1 << ceil_pow2(f.size() + g.size() - 1); std::vector a(n), b(n); std::copy(f.begin(), f.end(), a.begin()); std::copy(g.begin(), g.end(), b.begin()); internal::butterfly(a); internal::butterfly(b); for (int i = 0; i < n; i++) { a[i] *= b[i]; } internal::butterfly_inv(a); a.resize(f.size() + g.size() - 1); return a; } } // namespace ebi #line 2 "fps/fps.hpp" #line 7 "fps/fps.hpp" namespace ebi { template (*convolution)( const std::vector &, const std::vector &)> struct FormalPowerSeries : std::vector { private: using std::vector::vector; using std::vector::vector::operator=; using FPS = FormalPowerSeries; public: FPS operator+(const FPS &rhs) const noexcept { return FPS(*this) += rhs; } FPS operator-(const FPS &rhs) const noexcept { return FPS(*this) -= rhs; } FPS operator*(const FPS &rhs) const noexcept { return FPS(*this) *= rhs; } FPS operator/(const FPS &rhs) const noexcept { return FPS(*this) /= rhs; } FPS operator%(const FPS &rhs) const noexcept { return FPS(*this) %= rhs; } FPS operator+(const mint &rhs) const noexcept { return FPS(*this) += rhs; } FPS operator-(const mint &rhs) const noexcept { return FPS(*this) -= rhs; } FPS operator*(const mint &rhs) const noexcept { return FPS(*this) *= rhs; } FPS operator/(const mint &rhs) const noexcept { return FPS(*this) /= rhs; } FPS &operator+=(const FPS &rhs) noexcept { if (this->size() < rhs.size()) this->resize(rhs.size()); for (int i = 0; i < (int)rhs.size(); ++i) { (*this)[i] += rhs[i]; } return *this; } FPS &operator-=(const FPS &rhs) noexcept { if (this->size() < rhs.size()) this->resize(rhs.size()); for (int i = 0; i < (int)rhs.size(); ++i) { (*this)[i] -= rhs[i]; } return *this; } FPS &operator*=(const FPS &rhs) noexcept { *this = convolution(*this, rhs); return *this; } FPS &operator/=(const FPS &rhs) noexcept { int n = deg() - 1; int m = rhs.deg() - 1; if (n < m) { *this = {}; return *this; } *this = (*this).rev() * rhs.rev().inv(n - m + 1); (*this).resize(n - m + 1); std::reverse((*this).begin(), (*this).end()); return *this; } FPS &operator%=(const FPS &rhs) noexcept { *this -= *this / rhs * rhs; shrink(); return *this; } FPS &operator+=(const mint &rhs) noexcept { if (this->empty()) this->resize(1); (*this)[0] += rhs; return *this; } FPS &operator-=(const mint &rhs) noexcept { if (this->empty()) this->resize(1); (*this)[0] -= rhs; return *this; } FPS &operator*=(const mint &rhs) noexcept { for (int i = 0; i < deg(); ++i) { (*this)[i] *= rhs; } return *this; } FPS &operator/=(const mint &rhs) noexcept { mint inv_rhs = rhs.inv(); for (int i = 0; i < deg(); ++i) { (*this)[i] *= inv_rhs; } return *this; } FPS operator>>(int d) const { if (deg() <= d) return {}; FPS f = *this; f.erase(f.begin(), f.begin() + d); return f; } FPS operator<<(int d) const { FPS f = *this; f.insert(f.begin(), d, 0); return f; } FPS operator-() const { FPS g(this->size()); for (int i = 0; i < (int)this->size(); i++) g[i] = -(*this)[i]; return g; } FPS pre(int sz) const { return FPS(this->begin(), this->begin() + std::min(deg(), sz)); } FPS rev() const { auto f = *this; std::reverse(f.begin(), f.end()); return f; } FPS differential() const { int n = deg(); FPS g(std::max(0, n - 1)); for (int i = 0; i < n - 1; i++) { g[i] = (*this)[i + 1] * (i + 1); } return g; } FPS integral() const { int n = deg(); FPS g(n + 1); g[0] = 0; if (n > 0) g[1] = 1; auto mod = mint::mod(); for (int i = 2; i <= n; i++) g[i] = (-g[mod % i]) * (mod / i); for (int i = 0; i < n; i++) g[i + 1] *= (*this)[i]; return g; } FPS inv(int d = -1) const { int n = 1; if (d < 0) d = deg(); FPS g(n); g[0] = (*this)[0].inv(); while (n < d) { n <<= 1; g = (g * 2 - g * g * this->pre(n)).pre(n); } g.resize(d); return g; } FPS log(int d = -1) const { assert((*this)[0].val() == 1); if (d < 0) d = deg(); return ((*this).differential() * (*this).inv(d)).pre(d - 1).integral(); } FPS exp(int d = -1) const { assert((*this)[0].val() == 0); int n = 1; if (d < 0) d = deg(); FPS g(n); g[0] = 1; while (n < d) { n <<= 1; g = (g * (this->pre(n) - g.log(n) + 1)).pre(n); } g.resize(d); return g; } FPS pow(int64_t k, int d = -1) const { const int n = deg(); if (d < 0) d = n; if (k == 0) { FPS f(d); if (d > 0) f[0] = 1; return f; } for (int i = 0; i < n; i++) { if ((*this)[i] != 0) { mint rev = (*this)[i].inv(); FPS f = (((*this * rev) >> i).log(d) * k).exp(d); f *= (*this)[i].pow(k); f = (f << (i * k)).pre(d); if (f.deg() < d) f.resize(d); return f; } if (i + 1 >= (d + k - 1) / k) break; } return FPS(d); } int deg() const { return (*this).size(); } void shrink() { while ((!this->empty()) && this->back() == 0) this->pop_back(); } int count_terms() const { int c = 0; for (int i = 0; i < deg(); i++) { if ((*this)[i] != 0) c++; } return c; } std::optional sqrt(int d = -1) const; }; } // namespace ebi #line 2 "math/combination.hpp" #line 5 "math/combination.hpp" namespace ebi { template struct combination { combination(int n) : m(n), fact(n + 1), inv_fact(n + 1) { fact[0] = 1; for (int i = 1; i <= n; i++) { fact[i] = fact[i - 1] * i; } inv_fact[n] = fact[n].inv(); for (int i = n; i > 0; i--) { inv_fact[i - 1] = inv_fact[i] * i; } } mint operator()(int n, int k) const { assert(n <= m); if (k < 0 || n < k) return 0; return fact[n] * inv_fact[k] * inv_fact[n - k]; } mint f(int n) const { assert(n <= m); if (n < 0) return 0; return fact[n]; } mint inv_f(int n) const { assert(n <= m); if (n < 0) return 0; return inv_fact[n]; } mint inv(int n) const { assert(n <= m); return inv_fact[n] * fact[n-1]; } private: int m; std::vector fact, inv_fact; }; } // namespace ebi #line 2 "utility/modint.hpp" #line 6 "utility/modint.hpp" #line 8 "utility/modint.hpp" namespace ebi { template struct static_modint : internal::static_modint_base { private: using modint = static_modint; public: static constexpr int mod() { return m; } static constexpr modint raw(int v) { modint x; x._v = v; return x; } constexpr static_modint() : _v(0) {} constexpr static_modint(long long v) { v %= (long long)umod(); if (v < 0) v += (long long)umod(); _v = (unsigned int)v; } constexpr unsigned int val() const { return _v; } constexpr unsigned int value() const { return val(); } constexpr modint &operator++() { _v++; if (_v == umod()) _v = 0; return *this; } constexpr modint &operator--() { if (_v == 0) _v = umod(); _v--; return *this; } constexpr modint &operator+=(const modint &rhs) { _v += rhs._v; if (_v >= umod()) _v -= umod(); return *this; } constexpr modint &operator-=(const modint &rhs) { _v -= rhs._v; if (_v >= umod()) _v += umod(); return *this; } constexpr modint &operator*=(const modint &rhs) { unsigned long long x = _v; x *= rhs._v; _v = (unsigned int)(x % (unsigned long long)umod()); return *this; } constexpr modint &operator/=(const modint &rhs) { return *this = *this * rhs.inv(); } constexpr modint operator+() const { return *this; } constexpr modint operator-() const { return modint() - *this; } constexpr modint pow(long long n) const { assert(0 <= n); modint x = *this, res = 1; while (n) { if (n & 1) res *= x; x *= x; n >>= 1; } return res; } constexpr modint inv() const { assert(_v); return pow(umod() - 2); } friend modint operator+(const modint &lhs, const modint &rhs) { return modint(lhs) += rhs; } friend modint operator-(const modint &lhs, const modint &rhs) { return modint(lhs) -= rhs; } friend modint operator*(const modint &lhs, const modint &rhs) { return modint(lhs) *= rhs; } friend modint operator/(const modint &lhs, const modint &rhs) { return modint(lhs) /= rhs; } friend bool operator==(const modint &lhs, const modint &rhs) { return lhs.val() == rhs.val(); } friend bool operator!=(const modint &lhs, const modint &rhs) { return !(lhs == rhs); } private: unsigned int _v = 0; static constexpr unsigned int umod() { return m; } }; template std::istream &operator>>(std::istream &os, static_modint &a) { long long x; os >> x; a = x; return os; } template std::ostream &operator<<(std::ostream &os, const static_modint &a) { return os << a.val(); } using modint998244353 = static_modint<998244353>; using modint1000000007 = static_modint<1000000007>; } // namespace ebi #line 169 "a.cpp" namespace ebi { using mint = modint998244353; using FPS = FormalPowerSeries; void main_() { int n; std::cin >> n; FPS f(n+1); combination comb(n); rep(i,0,n+1) { f[i] = (i + 1) * comb.inv_f(i); } mint ans = f.pow(n)[n-2] * comb.f(n-2) / mint(n).pow(n-2); std::cout << ans.val() << '\n'; } } // namespace ebi int main() { std::cout << std::fixed << std::setprecision(15); std::cin.tie(nullptr); std::ios::sync_with_stdio(false); int t = 1; // std::cin >> t; while (t--) { ebi::main_(); } return 0; }