#include using namespace std; //入力が必ず-mod struct modint{ //mod変更が不可能. public: long long v = 0; static void setmod(int m){} //飾り. static constexpr long long getmod(){return mod;} modint(){v = 0;} modint(int a){v = a<0?a+mod:a;} modint(long long a){v = a<0?a+mod:a;} modint(unsigned int a){v = a;} modint(unsigned long long a){v = a;} long long val()const{return v;} modint &operator=(const modint &b) = default; modint operator+()const{return (*this);} modint operator-()const{return modint(0)-(*this);} modint operator+(const modint b)const{return modint(v)+=b;} modint operator-(const modint b)const{return modint(v)-=b;} modint operator*(const modint b)const{return modint(v)*=b;} modint operator/(const modint b)const{return modint(v)/=b;} modint operator+=(const modint b){ v += b.v; if(v >= mod) v -= mod; return *this; } modint operator-=(const modint b){ v -= b.v; if(v < 0) v += mod; return *this; } modint operator*=(const modint b){v = v*b.v%mod; return *this;} modint operator/=(modint b){ //b!=0 mod素数が必須. if(b == 0) assert(false); int left = mod-2; while(left){if(left&1) *this *= b; b *= b; left >>= 1;} return *this; } modint operator++(){*this += 1; return *this;} modint operator--(){*this -= 1; return *this;} modint operator++(int){*this += 1; return *this;} modint operator--(int){*this -= 1; return *this;} bool operator==(const modint b)const{return v == b.v;} bool operator!=(const modint b)const{return v != b.v;} bool operator>(const modint b)const{return v > b.v;} bool operator>=(const modint b)const{return v >= b.v;} bool operator<(const modint b)const{return v < b.v;} bool operator<=(const modint b)const{return v <= b.v;} modint pow(long long n)const{ modint ret = 1,p = v; if(n < 0) p = p.inv(),n = -n; while(n){ if(n&1) ret *= p; p *= p; n >>= 1; } return ret; } modint inv()const{return modint(1)/v;} //素数mod必須. }; template //modが入力で与えられる場合. struct dynamic_modint{ //mod変更が可能 最初にsetmod必須 idxで複数個所持が可能. private: static int mod; public: long long v = 0; static constexpr long long getmod(){return mod;} static void setmod(int m){ assert(m > 0); mod = m; } dynamic_modint(){v = 0;} dynamic_modint(int a){v = a<0?a+mod:a;} dynamic_modint(long long a){v = a<0?a+mod:a;} dynamic_modint(unsigned int a){v = a;} dynamic_modint(unsigned long long a){v = a;} long long val()const{return v;} dynamic_modint &operator=(const dynamic_modint &b) = default; dynamic_modint operator+()const{return (*this);} dynamic_modint operator-()const{return dynamic_modint(0)-(*this);} dynamic_modint operator+(const dynamic_modint b)const{return dynamic_modint(v)+=b;} dynamic_modint operator-(const dynamic_modint b)const{return dynamic_modint(v)-=b;} dynamic_modint operator*(const dynamic_modint b)const{return dynamic_modint(v)*=b;} dynamic_modint operator/(const dynamic_modint b)const{return dynamic_modint(v)/=b;} dynamic_modint operator+=(const dynamic_modint b){ v += b.v; if(v >= mod) v -= mod; return *this; } dynamic_modint operator-=(const dynamic_modint b){ v -= b.v; if(v < 0) v += mod; return *this; } dynamic_modint operator*=(const dynamic_modint b){v = v*b.v%mod; return *this;} dynamic_modint operator/=(dynamic_modint b){ //b!=0 mod素数が必須. if(b == 0) assert(false); int left = mod-2; while(left){if(left&1) *this *= b; b *= b; left >>= 1;} return *this; } dynamic_modint operator++(){*this += 1; return *this;} dynamic_modint operator--(){*this -= 1; return *this;} dynamic_modint operator++(int){*this += 1; return *this;} dynamic_modint operator--(int){*this -= 1; return *this;} bool operator==(const dynamic_modint b)const{return v == b.v;} bool operator!=(const dynamic_modint b)const{return v != b.v;} bool operator>(const dynamic_modint b)const{return v > b.v;} bool operator>=(const dynamic_modint b)const{return v >= b.v;} bool operator<(const dynamic_modint b)const{return v < b.v;} bool operator<=(const dynamic_modint b)const{return v <= b.v;} dynamic_modint pow(long long n)const{ dynamic_modint ret = 1,p = v; if(n < 0) p = p.inv(),n = -n; while(n){ if(n&1) ret *= p; p *= p; n >>= 1; } return ret; } dynamic_modint inv()const{return dynamic_modint(1)/v;} //素数mod必須. }; template int dynamic_modint::mod=998244353; using mint = modint<1234567891>; //using mint = modint<1000000007>; //using mint = dynamic_modint<0>; namespace to_fold{ __int128_t safemod(__int128_t a,long long m){a %= m; if(a < 0) a += m; return a;} pair invgcd(long long a,long long b){ //return {gcd(a,b),x} (xa≡g(mod b)) a = safemod(a,b); if(a == 0) return {b,0}; long long x = 0,y = 1,memob = b; while(a){ long long q = b/a; b -= a*q; swap(x,y); y -= q*x; swap(a,b); } if(x < 0) x += memob/b; return {b,x}; } template long long Garner(const vector &A,const vector &M){ __int128_t mulM = 1,x = A.at(0)%M.at(0); //Mの要素のペア互いに素必須. for(int i=1; i struct fftinfo{ static bool First; static mint g,sum_e[30],sum_ie[30]; //sum_e[i]=Π[j=0~i-1]ies[j] * es[i],sum_ie[i]=Π[i=0~j-1]es[j] * ies[i]. static mint divpow2[30]; //div[i] = 1/(2^i). static mint Zeta[30]; fftinfo(){ if(!First) return; First = false; const long long mod = mint::getmod(); if(mod == 998244353) g = 3; else if(mod == 754974721) g = 11; else if(mod == 167772161) g = 3; else if(mod == 469762049) g = 3; else assert(false); //現状RE. mint es[30],ies[30]; //es[i]^(2^(2+i))=1. int cnt2 = countzero(mod-1); mint e = g.pow((mod-1)>>cnt2),ie = e.inv(); for(int i=cnt2; i>=2; i--){ //e^(2^i)=1; es[i-2] = e,e *= e; ies[i-2] = ie,ie *= ie; } mint rot = 1; for(int i=0; i<=cnt2-2; i++) sum_e[i] = es[i]*rot,rot *= ies[i]; rot = 1; for(int i=0; i<=cnt2-2; i++) sum_ie[i] = ies[i]*rot,rot *= es[i]; mint div2n = 1,div2 = mint(1)/2; for(int i=0; i<30; i++) divpow2[i] = div2n,div2n *= div2; for(int i=0; i<=cnt2; i++) Zeta[i] = g.pow((mod-1)/(2< bool fftinfo::First=true; template mint fftinfo::g; template mint fftinfo::sum_e[30]; template mint fftinfo::sum_ie[30]; template mint fftinfo::divpow2[30]; template mint fftinfo::Zeta[30]; template void NTT(vector &A){ //ACLを超参考にしてる. int n = A.size(); assert((n&-n) == n); fftinfo info; int h = countzero(n); for(int ph=1; ph<=h; ph++){ int w = 1<<(ph-1),p = 1<<(h-ph); mint rot = 1; for(int s=0; s void INTT(vector &A){ int n = A.size(); assert((n&-n) == n); fftinfo info; const unsigned int mod = mint::getmod(); int h = countzero(n); for(int ph=h; ph>0; ph--){ int w = 1<<(ph-1),p = 1<<(h-ph); mint irot = 1; for(int s=0; s vector convolution(vector A,vector B){ //mintじゃないのを突っ込まないように!!!. int siza = A.size(),sizb = B.size(),sizc = siza+sizb-1,N = 1; if(siza == 0 || sizb == 0) return {}; if(min(siza,sizb) <= 60){ //naive. vector ret(sizc); if(siza >= sizb){for(int i=0; i convolution_ll(const vector &A,const vector &B){ //long longに収まる範囲. int siza = A.size(),sizb = B.size(),sizc = siza+sizb-1; if(siza == 0 || sizb == 0) return {}; vector ret(sizc); if(min(siza,sizb) <= 200){ //naive 200はやばい?. vector ret(sizc); if(siza >= sizb){for(int i=0; i; using mint2 = modint; using mint3 = modint; vector a1(siza),b1(sizb); vector a2(siza),b2(sizb); vector a3(siza),b3(sizb); for(int i=0; i C1 = convolution(a1,b1); for(int i=0; i C2 = convolution(a2,b2); for(int i=0; i C3 = convolution(a3,b3); vector offset = {0,0,m1m2m3,2*m1m2m3,3*m1m2m3}; for(int i=0; i vector convolution_llmod(const vector &A,const vector &B){ int siza = A.size(),sizb = B.size(),sizc = siza+sizb-1; if(siza == 0 || sizb == 0) return {}; vector ret(sizc); if(min(siza,sizb) <= 200){ for(int i=0; i; using mint2 = modint; using mint3 = modint; vector a1(siza),b1(sizb); vector a2(siza),b2(sizb); vector a3(siza),b3(sizb); for(int i=0; i C1 = convolution(a1,b1); for(int i=0; i C2 = convolution(a2,b2); for(int i=0; i C3 = convolution(a3,b3); for(int i=0; i A = {C1.at(i).v,C2.at(i).v,C3.at(i).v}; vector M = {mod1,mod2,mod3}; ret.at(i) = Garner(A,M); } return ret; } vector convolution_int(const vector &A,const vector &B){ //intに収まる範囲. if(A.size() == 0 || B.size() == 0) return {}; vector ret; if(min(A.size(),B.size()) <= 60){ ret.resize(A.size()+B.size()-1); for(int i=0; i; vector X(A.size()),Y(B.size()),Z; for(int i=0; i void NTTdoubling(vector &A){ //NTTの原理を忘れているため何やってるのか意味が分からない NTT-friendly専用. //INTT->resize(2倍)->NTTの代わりにcopy->INTT->謎の操作->NTT->push sizeが小さい時は効率悪いらしいよ. int n = A.size(); fftinfo info; vector B = A; INTT(B); mint rot = 1,zeta = info.Zeta[countzero(n)]; for(auto &v : B) v *= rot,rot *= zeta; NTT(B); A.reserve(n<<1); for(auto &v : B) A.push_back(v); } bool isNTTfriendly(long long mod){ if(mod == 998244353 || mod == 754974721 || mod == 16777216 || mod == 469762049) return true; return false; //現状false 原子根求める機能を追加してから. int have2 = countzero(mod-1); return have2 >= 20;//とりあえず2^20でokとする; } } using namespace to_fold; template //実質mintだけ?. struct FormalPowerSeries:vector{ //NTT-friendly素数だけ じゃなくてもいいけど全部書き直せ!. using vector::vector; using fps = FormalPowerSeries; FormalPowerSeries(const vector &A){(*this) = A;} //重要なところは某のほぼパクリ. fps operator++(){*this += 1; return *this;} fps operator--(){*this -= 1; return *this;} fps operator++(int){*this += 1; return *this;} fps operator--(int){*this -= 1; return *this;} fps operator+(const fps &b) const {return fps(*this)+=b;} fps operator+(const T &b) const {return fps(*this)+=b;} fps operator-(const fps &b) const {return fps(*this)-=b;} fps operator-(const T &b) const {return fps(*this)-=b;} fps operator*(const fps &b){return fps(*this)*=b;} fps operator*(const T &b) const {return fps(*this)*=b;} fps operator/(const fps &b) const {return fps(*this)/=b;} fps operator%(const fps &b) const {return fps(*this)%=b;} fps operator>>(const unsigned int b) const {return fps(*this)>>=b;} fps operator<<(const unsigned int b) const {return fps(*this)<<=b;} fps operator-()const{ //-1倍; fps ret = (*this); for(auto &v : ret) v = -v; return ret; } bool operator==(const fps &b)const{ if((*this).size() != b.size()) return false; for(int i=0; i<(*this).size(); i++) if((*this).at(i) != b.at(i)) return false; return true; } bool operator!=(const fps &b)const{return !((*this)==b);} fps &operator+=(const fps &b){ //Cix^i = (Ai+Bi)x^i. O(n). if((*this).size() < b.size()) (*this).resize(b.size(),0); for(int i=0; i re; if(isNTTfriendly(mint::getmod())) re = convolution((*this),b); //NTT-friendlyならok 現在は4種以外認めない. else re = convolution_llmod((*this),b); (*this).resize(re.size()); for(int i=0; i>=(const unsigned int &b){//b<0は対象外. 先頭b項を削除. O(n) if((*this).size() <= b) (*this).clear(); else (*this).erase((*this).begin(),(*this).begin()+b); return *this; } fps &operator<<=(const unsigned int &b){//b<0は対象外. 先頭b項に0を挿入. O(n) (*this).insert((*this).begin(),b,0); return *this; } fps &operator%=(const fps &b){ //多項式の余り. O(nlogn) (*this) -= (*this)/b*b; del0(); return (*this); } fps &operator/=(const fps &b){ //多項式としての除算 O(nlogn). assert(b.size() > 0); //分母の末尾0は駄目. T check = b.back(); assert(check != 0); del0(); //分子の末尾0は消して許容. if((*this).size() < b.size()){ (*this).clear(); return *this; } int n = (*this).size()-b.size()+1; if(b.size() <= 64){ //愚直. fps G(b); assert(G.size() > 0); T div = G.back().inv(); for (auto &v : G) v *= div; int deg = (*this).size()-G.size()+1; fps Q(deg); for(int i=deg-1; i>=0; i--){ Q[i] = (*this).at(i+G.size()-1); for(int k=0; k> P; for(int i=0; i> P; if((*this).at(0) != 1) div = T((*this).at(0)).inv(); for(int i=1; i= k) ret.at(i) -= v*ret.at(i-k); //-xが+ret[i-1]に対応. if(div != 1) for(auto &v : ret) v *= div; return ret; } fps inv_sparse(const fps &b,int deg = -1)const{ //f/gを返す 1/fでは分母だがこれは分子に注意. int n = (*this).size(),m = b.size(); if(deg == -1) deg = n; assert(b.at(0) != 0); T div = 1; vector> P; if(b.at(0) != 1) div = T(b.at(0)).inv(); for(int i=1; i= k) ret.at(i) -= v*ret.at(i-k); if(div != 1) for(auto &v : ret) v *= div; return ret; } fps log_sparse(int deg = -1){ //log(f)を返す O(N*非0). //logf = ∫(f'/f) inv,1/f*(f')がO(N*非0) 他はO(N). assert((*this).size()&&(*this).at(0)==1); if(deg == -1) deg = (*this).size(); fps ret = (*this).diff(); ret = ((*this).inv_sparse(deg)).multi_sparse(ret); return ret.inte().prefix(deg); } fps exp_sparse(int deg = -1)const{ //exp(f)を返す O(N*非0). //(expf)'=(f')*exp(f)より低次から決まる. //[x^0]expf=1より左辺のx^0の係数が求まる->expfのx^1の係数が求まる->... if(deg == -1) deg = (*this).size(); fps ret(deg); if((*this).size() == 0){ if(deg > 0) ret.at(0) = 1; return ret; } assert((*this).at(0) == 0); if(deg == 1) return fps{1}; ret.at(0) = 1; ret.at(1) = 1; const long long mod = mint::getmod(); for(int i=2; i> P; for(int i=1; i<(*this).size(); i++) if((*this).at(i) != 0) P.emplace_back(pair{i-1,(*this).at(i)*i}); for(int i=0; i 0) ret.at(0) = 1; return ret; } for(int t=0; t> P; for(int i=t+1; i 1) ret.at(1) = 1; const long long mod = mint::getmod(); for(int i=2; i n+1) break; if(i > 0 && i<=n+1) now += mulK*ret.at(n+1-i)*i*v; if(i > 0 && i <= n) now -= v*(n+1-i)*ret.at(n+1-i); } ret.at(n+1) *= now; } ret *= T((*this).at(t)).pow(K); return (ret<<(t*K)).prefix(deg); } if(K >= deg || (t+1)*K >= deg) break; } return fps(deg,0); } fps diff()const{ //微分 nx^(n-1) = (x^n)' O(n). int n = (*this).size(); if(n <= 1) return {}; fps ret(n-1); T multi = 1; for(int i=1; i divi; //invと衝突回避用 mintでiの逆元. const long long mod = mint::getmod(); divi.resize(deg*2); divi.at(1) = 1; for(int i=2; i void { //inplaceで積分. int n = f.size(); f.insert(f.begin(),0); for(int i=1; i<=n; i++) f.at(i) *= divi.at(i); }; auto differential = [&](fps &f) -> void { //inplaceで微分. if(f.size() == 0) return; f.erase(f.begin()); T multi = 0; for(int i=0; i 1) f.push_back((*this).at(1)); else f.push_back(0); for(int m=2; m 0) ret.at(0) = 1; return ret; } for(int i=0; i>i).log(deg)*(K%mod)).exp(deg); ret *= T((*this).at(i)).pow(K); //[x^i]f^Kの分. ret = (ret<<(i*K)).prefix(deg); //*x^(i*k)の分. return ret; } if(K >= deg || (i+1)*K >= deg) break; //((i+1)*K)乗未満は0確定 int128回避用にK>=deg(degがllはやばい). } return fps(deg,0); //fの係数全て0なら係数全て0. } fps prefix(int siz)const{ //先頭siz項を返す なかったら0埋め. O(siz). fps ret((*this).begin(),(*this).begin()+min((int)(*this).size(),siz)); if(ret.size() < siz) ret.resize(siz,0); return ret; } void del0(){ //末尾の0を消す O(n). while((*this).size() && (*this).back() == 0) (*this).pop_back(); } fps rev()const{ //ひっくり返す O(n). fps ret(*this); reverse(ret.begin(),ret.end()); return ret; } pair getQR(const fps &b)const{ //多項式の商と余りを同時に得る O(nlogn). fps Q = (*this)/b,R = (*this)-Q*b; R.del0(); return {Q,R}; } fps cumulativeNtimes(int N,T b,int deg=-1){ //1/(1-bx)^Nをdeg次まで返す 指定なしはN次まで. //負の二項定理を使う. 1/(1-x)^N=Σ[i=0~∞]((n+i-1) choose i)(bx^i); //fps{}.cumulativeNtime()で無理やり関数を呼び出す. assert(N <= 0); //N=0も駄目? {1}を返すべき所{0}になる. if(deg == -1) deg = N+1; int Limit = N+deg; //Limit 必要なサイズ fac->x! facinv->1/x! inv->1/x. long long mod = mint::getmod(),invstart = min((int)mod-1,Limit); vector FAC(Limit+1,1); for(int i=1; i<=Limit; i++) FAC.at(i) = FAC.at(i-1)*i; vector FACinv(Limit+1); FACinv.at(invstart) = FAC.at(invstart).inv(); for(int i=invstart-1; i>=0; i--) FACinv.at(i) = FACinv.at(i+1)*(i+1); auto nCr = [&](int n, int r) -> T { if(n < r || r < 0 || n < 0) return 0; return FAC.at(n)*FACinv.at(r)*FACinv.at(n-r); }; fps ret(deg); T value = 1; for(int i=0; ix! facinv->1/x! inv->1/x. long long invstart = min((int)mod-1,deg); vector fac(deg+1,1); for(int i=1; i<=deg; i++) fac.at(i) = fac.at(i-1)*i; vector facinv(deg+1); facinv.at(invstart) = fac.at(invstart).inv(); for(int i=invstart-1; i>=0; i--) facinv.at(i) = facinv.at(i+1)*(i+1); fps X(deg),Y(deg); for(int i=0; i; template vector ProductPoly(vector> Fs){ //ΠFiを返す 返り値の次数をdをしてO(dlog^2d). int n = Fs.size(); if(n == 0) return {1}; if(n == 1) return Fs.at(0); auto f = [&](auto f,int l,int r) -> vector { if(l+1 == r) return Fs.at(l); return convolution(f(f,l,(l+r)/2),f(f,(l+r)/2,r)); }; return f(f,0,n); } fps ProductPoly(vector Fs){ //ΠFiを返す 返り値の次数をdをしてO(dlog^2d). int n = Fs.size(); if(n == 0) return {1}; if(n == 1) return Fs.at(0); auto f = [&](auto f,int l,int r) -> fps { if(l+1 == r) return Fs.at(l); return f(f,l,(l+r)/2)*f(f,(l+r)/2,r); }; return f(f,0,n); } mint BostanMori(long long N,fps P,fps Q){ P.del0(); Q.del0(); int K = Q.size(); mint ret = 0; if(P.size() >= Q.size()){ //deg(P)>=deg(Q)の時. auto R = P/Q; P -= R*Q; P.del0(); if(N < R.size()) ret += R.at(N); } if(P.size() == 0) return ret; if(isNTTfriendly(mint::getmod())){ //NTT-friendly int n = 1; while(n < K) n <<= 1; P.resize(2*n); Q.resize(2*n); NTT(P),NTT(Q); vector S(n),T(n); vector Bitrev(n); //ビットリバース. for(int i=0; i>1; Bitrev.at(i) += (Bitrev.at(i>>1)>>1); } fftinfo info; mint dw = info.g.inv().pow((mint::getmod()-1)/(n<<1)),Div2 = mint(1)/2; while(N){ mint div2 = Div2; S.resize(n),T.resize(n); for(int i=0; i<(n<<1); i+=2) T.at(i>>1) = Q.at(i)*Q.at(i+1); //Q(x)Q(-x)の偶数次. if(N&1){ //P(x)Q(-x)の奇数次. for(auto i : Bitrev){ S.at(i) = (P.at(i<<1)*Q.at((i<<1)+1)-P.at((i<<1)+1)*Q.at(i<<1))*div2; div2 *= dw; //これ分からん. } } else{ //P(x)Q(-x)の偶数次. for(int i=0; i<(n<<1); i+=2) S.at(i>>1) = (P.at(i)*Q.at(i+1)+P.at(i+1)*Q.at(i))*div2; } swap(P,S),swap(Q,T); N >>= 1; if(N < n) break; NTTdoubling(P),NTTdoubling(Q); } INTT(P),INTT(Q); Q = Q.inv(); for(int i=0; i<=N; i++) ret += P.at(i)*Q.at(N-i); //ret+=[x^N]P/Q return ret; } else{ //P(x)/Q(x)=P(x)Q(-x)/Q(x)Q(-x) 分母の奇数次は全部0になる. P.resize(K-1); bool skip = false; while(N){ if(!skip){ auto memo = Q; fps Q2 = Q; for(int i=1; i>1) = Q.at(i); //偶数次しかないので次数/2をする. Q.resize((Q.size()+1)>>1); if(memo == Q){ skip = true; for(int i=1; i>1) = P.at(i); P.resize(P.size()>>1); } else{ //Nthが偶数. for(int i=0; i>1) = P.at(i); P.resize((P.size()+1)>>1); } N >>= 1; } return ret+P.at(0); } } int main(){ ios_base::sync_with_stdio(false); cin.tie(nullptr); long long N,M; cin >> N >> M; vector Fs,Gs; Fs.reserve(N*10),Gs.reserve(N*10); for(int i=0; i> a; fps f(a+1); f.at(0) = 1,f.at(a) = -1; Gs.emplace_back(f); } fps G = ProductPoly(Gs); cout << BostanMori(M,{1},G).v << endl; }