#pragma region Macros #include #include #if defined(LOCAL) || defined(_DEBUG) #include "debug.hpp" #else #define O(...) #define START() #define STOP() #define MEMORY() #endif using namespace std; #define REP(i, n) for(int i=0, i##_len=(n); i=0; --i) #define FOR(i, n, m) for(int i=(m), i##_len=(n); ibool chmax(T &a, const U &b) { if (a<(T)b) { a=(T)b; return 1; } return 0; } templatebool chmin(T &a, const U &b) { if (b<(T)a) { a=(T)b; return 1; } return 0; } #define vec vector #define umap unordered_map #define uset unordered_set using ll = long long; using ld = long double; using P = pair; using Tup = tuple; using vl = vec; #define fi first #define se second #define el endl constexpr ll INF = numeric_limits::max()/2-1; template istream &operator>>(istream &stream, vec& o){REP(i, o.size())stream >> o[i];return stream;} template istream &operator>>(istream &stream, pair& o){cin >> o.fi >> o.se; return stream;} namespace myinput { void input() {} template void input(T&& o, Ts&&... args){cin >> o;input(forward(args)...);} void assign_vl(size_t siz) {}; template void assign_vl(size_t siz, T&& o, Ts&&... args){o.resize(siz);assign_vl(siz, forward(args)...);} void input_horizon_sub(size_t index) {}; template void input_horizon_sub(size_t index, T&& o, Ts&&... args) {cin>>o[index];input_horizon_sub(index, forward(args)...);} template void input_horizon(size_t siz, Ts&&... args){REP(i, siz) input_horizon_sub(i, forward(args)...);} } #define _I(T, ...) ;myinput::input(__VA_ARGS__); #define I(T, ...) ;T __VA_ARGS__;_I(T, __VA_ARGS__); #define _Iv(T, siz, ...) ;myinput::assign_vl(siz, __VA_ARGS__);myinput::input(__VA_ARGS__); #define Iv(T, siz, ...) ;vec __VA_ARGS__;_Iv(T, siz, __VA_ARGS__); #define _Ih(T, siz, ...) ;myinput::assign_vl(siz, __VA_ARGS__);myinput::input_horizon(siz, __VA_ARGS__); #define Ih(T, siz, ...) ;vec __VA_ARGS__;_Ih(T, siz, __VA_ARGS__); #pragma endregion void Main(); int main(){ std::cin.tie(nullptr); std::cout << std::fixed << std::setprecision(15); Main(); MEMORY(); return 0; } // mod Pのための型 #pragma region modint template struct modint{ protected: ll v=0; public: //コンストラクタ modint(ll x=0){while(x<0)x+=m;v=x%m;} modint(const modint &r){v=r.val();} //算術演算子(単項) modint operator -(){return modint(-v);} modint& operator ++(){if(++v>=m)v-=m; return *this;} modint operator ++(int){modint t = *this; ++*this; return t;} modint& operator --(){if(--v<0)v+=m; return *this;} modint operator --(int){modint t = *this; --*this; return t;} //算術演算子(二項) friend modint operator +(const modint &l, const modint &r){return modint(l)+=r;} friend modint operator -(const modint &l, const modint &r){return modint(l)-=r;} friend modint operator *(const modint &l, const modint &r){return modint(l)*=r;} friend modint operator /(const modint &l, const modint &r){return modint(l)/=r;} // キャスト演算子 explicit operator int() const {return val();} explicit operator ll() const {return val();} //代入演算子 modint &operator +=(const modint &r){ v+=r.val(); if(v>=m)v-=m; return *this; } modint &operator -=(const modint &r){ if(v(const modint &l, const modint& r){return l.val()>r.val();} friend bool operator !=(const modint &l, const modint& r){return l.val()!=r.val();} // 各種関数 int val() const{return v;} constexpr static ll mod(){return m;} static modint raw(ll x){modint r;r.v=x;return r;} modint inv() const{ ll a=v,b=m,u=1,v=0; while(b){ ll t=a/b; a-=t*b;swap(a,b); u-=t*v;swap(u,v); } u %= m; if (u < 0) u += m; return u; } modint pow(ll n) const{ modint ret = 1, x(v); while (n > 0) { if (n & 1) ret *= x; x *= x; n >>= 1; } return ret; } //入出力ストリーム friend istream &operator>>(istream &is,modint& x){ll t;is>>t;x=t;return (is);} friend ostream &operator<<(ostream &os,const modint& x){return os<; using modint998244353 = modint<998244353>; #pragma endregion using mint = modint998244353; void Main(){ I(ll, n, k); mint x = (k * (k-1)) / 2; x *= n; x *= 2; mint y = mint(k).pow(n); O(x, y); cout << x/y << el; }