#line 1 "main.cpp" /** * @title Template */ #include #include #include #include #include #include #include #line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/other/range.cpp" #line 4 "/Users/kodamankod/Desktop/cpp_programming/Library/other/range.cpp" class range { struct iter { std::size_t itr; constexpr iter(std::size_t pos) noexcept: itr(pos) { } constexpr void operator ++ () noexcept { ++itr; } constexpr bool operator != (iter other) const noexcept { return itr != other.itr; } constexpr std::size_t operator * () const noexcept { return itr; } }; struct reviter { std::size_t itr; constexpr reviter(std::size_t pos) noexcept: itr(pos) { } constexpr void operator ++ () noexcept { --itr; } constexpr bool operator != (reviter other) const noexcept { return itr != other.itr; } constexpr std::size_t operator * () const noexcept { return itr; } }; const iter first, last; public: constexpr range(std::size_t first, std::size_t last) noexcept: first(first), last(std::max(first, last)) { } constexpr iter begin() const noexcept { return first; } constexpr iter end() const noexcept { return last; } constexpr reviter rbegin() const noexcept { return reviter(*last - 1); } constexpr reviter rend() const noexcept { return reviter(*first - 1); } }; /** * @title Range */ #line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/modular.cpp" #line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/mod_inv.cpp" #line 4 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/mod_inv.cpp" #include constexpr std::pair mod_inv(int64_t a, int64_t b) { if ((a %= b) == 0) return { b, 0 }; int64_t s = b, t = (a < 0 ? a + b : a); int64_t m0 = 0, m1 = 1, tmp = 0; while (t > 0) { const auto u = s / t; s -= t * u; m0 -= m1 * u; tmp = s; s = t; t = tmp; tmp = m0; m0 = m1; m1 = tmp; } return { s, (m0 < 0 ? m0 + b / s : m0) }; } /** * @title Extended GCD */ #line 4 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/modular.cpp" #line 8 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/modular.cpp" #include template class modular { public: using value_type = uint32_t; using cover_type = uint64_t; static constexpr uint32_t mod() { return Modulus::mod(); } template static constexpr value_type normalize(T value_) noexcept { if (value_ < 0) { value_ = -value_; value_ %= mod(); if (value_ == 0) return 0; return mod() - value_; } return value_ % mod(); } private: value_type value; template * = nullptr> constexpr modular inverse_helper() const noexcept { return power(*this, mod() - 2); } template * = nullptr> constexpr modular inverse_helper() const noexcept { const auto tmp = mod_inv(value, mod()); assert(tmp.first == 1); return modular(tmp.second); } public: constexpr modular() noexcept : value(0) { } template explicit constexpr modular(T value_) noexcept : value(normalize(value_)) { } template explicit constexpr operator T() const noexcept { return static_cast(value); } constexpr value_type get() const noexcept { return value; } constexpr value_type &extract() noexcept { return value; } constexpr modular operator - () const noexcept { return modular(mod() - value); } constexpr modular operator ~ () const noexcept { return inverse(*this); } constexpr modular operator + (const modular &rhs) const noexcept { return modular(*this) += rhs; } constexpr modular& operator += (const modular &rhs) noexcept { if ((value += rhs.value) >= mod()) value -= mod(); return *this; } constexpr modular operator - (const modular &rhs) const noexcept { return modular(*this) -= rhs; } constexpr modular& operator -= (const modular &rhs) noexcept { if ((value += mod() - rhs.value) >= mod()) value -= mod(); return *this; } constexpr modular operator * (const modular &rhs) const noexcept { return modular(*this) *= rhs; } constexpr modular& operator *= (const modular &rhs) noexcept { value = (cover_type) value * rhs.value % mod(); return *this; } constexpr modular operator / (const modular &rhs) const noexcept { return modular(*this) /= rhs; } constexpr modular& operator /= (const modular &rhs) noexcept { return (*this) *= inverse(rhs); } constexpr bool zero() const noexcept { return value == 0; } constexpr bool operator == (const modular &rhs) const noexcept { return value == rhs.value; } constexpr bool operator != (const modular &rhs) const noexcept { return value != rhs.value; } friend std::ostream& operator << (std::ostream &stream, const modular &rhs) { return stream << rhs.value; } friend constexpr modular inverse(const modular &val) noexcept { return val.inverse_helper(); } friend constexpr modular power(modular val, cover_type exp) noexcept { modular res(1); for (; exp > 0; exp >>= 1, val *= val) if (exp & 1) res *= val; return res; } }; template struct static_modulus { static constexpr uint32_t mod() noexcept { return Mod; } static constexpr bool is_prime = IsPrime; }; template struct dynamic_modulus { static uint32_t &mod() noexcept { static uint32_t val = 0; return val; } static constexpr bool is_prime = IsPrime; }; template using mint32_t = modular>; using rmint32_t = modular>; /* * @title Modint */ #line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/factorials.cpp" #include #line 6 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/factorials.cpp" template class factorials { public: using value_type = T; public: std::array fact{}; std::array fact_inv{}; factorials() { fact.front() = value_type(1); for (size_t i = 1; i <= N; ++i) { fact[i] = fact[i - 1] * value_type(i); } fact_inv.back() = value_type(1) / fact.back(); for (size_t i = N; i > 0; --i) { fact_inv[i - 1] = fact_inv[i] * value_type(i); } } value_type operator () (size_t n, size_t r) const { assert(n <= N); assert(n >= r); return fact[n] * fact_inv[n - r] * fact_inv[r]; } }; /** * @title Factorial */ #line 17 "main.cpp" using i32 = std::int32_t; using i64 = std::int64_t; using u32 = std::uint32_t; using u64 = std::uint64_t; using isize = std::ptrdiff_t; using usize = std::size_t; constexpr i32 inf32 = (i32(1) << 30) - 1; constexpr i64 inf64 = (i64(1) << 62) - 1; using Fp = mint32_t<998244353>; factorials fact; int main() { usize N; std::cin >> N; Fp ans; for (auto i: range(0, N - 1)) { ans += fact.fact[N - 2] * fact.fact_inv[(N - 2) - i] * power(Fp(N), (N - 2) - i) * fact(N, i); } std::cout << ans / power(Fp(N), N - 2) << '\n'; return 0; }