結果

問題 No.3213 depth max K
ユーザー Taiki0715
提出日時 2025-07-25 22:28:44
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 27 ms / 2,000 ms
コード長 20,786 bytes
コンパイル時間 3,530 ms
コンパイル使用メモリ 310,160 KB
実行使用メモリ 7,716 KB
最終ジャッジ日時 2025-07-25 22:28:51
合計ジャッジ時間 5,155 ms
ジャッジサーバーID
(参考情報)
judge5 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 3
other AC * 41
権限があれば一括ダウンロードができます

ソースコード

diff #

#include <bits/stdc++.h>
using namespace std;
using ll=long long;
using ull=unsigned long long;
using P=pair<ll,ll>;
template<typename T>using minque=priority_queue<T,vector<T>,greater<T>>;
template<typename T>bool chmax(T &a,const T &b){return (a<b?(a=b,true):false);}
template<typename T>bool chmin(T &a,const T &b){return (a>b?(a=b,true):false);}
template<typename T1,typename T2>istream &operator>>(istream &is,pair<T1,T2>&p){is>>p.first>>p.second;return is;}
template<typename T1,typename T2,typename T3>istream &operator>>(istream &is,tuple<T1,T2,T3>&a){is>>std::get<0>(a)>>std::get<1>(a)>>std::get<2>(a);return is;}
template<typename T,size_t n>istream &operator>>(istream &is,array<T,n>&a){for(auto&i:a)is>>i;return is;}
template<typename T>istream &operator>>(istream &is,vector<T> &a){for(auto &i:a)is>>i;return is;}
template<typename T1,typename T2>void operator++(pair<T1,T2>&a,int n){a.first++,a.second++;}
template<typename T1,typename T2>void operator--(pair<T1,T2>&a,int n){a.first--,a.second--;}
template<typename T>void operator++(vector<T>&a,int n){for(auto &i:a)i++;}
template<typename T>void operator--(vector<T>&a,int n){for(auto &i:a)i--;}
#define overload3(_1,_2,_3,name,...) name
#define rep1(i,n) for(int i=0;i<(int)(n);i++)
#define rep2(i,l,r) for(int i=(int)(l);i<(int)(r);i++)
#define rep(...) overload3(__VA_ARGS__,rep2,rep1)(__VA_ARGS__)
#define reps(i,l,r) rep2(i,l,r)
#define all(x) x.begin(),x.end()
#define pcnt(x) __builtin_popcountll(x)
#define fin(x) return cout<<(x)<<'\n',static_cast<void>(0)
#define yn(x) cout<<((x)?"Yes\n":"No\n")
#define uniq(x) sort(all(x)),x.erase(unique(all(x)),x.end())
template<typename T>
inline int fkey(vector<T>&z,T key){return lower_bound(z.begin(),z.end(),key)-z.begin();}
ll myceil(ll a,ll b){return (a+b-1)/b;}
template<typename T,size_t n,size_t id=0>
auto vec(const int (&d)[n],const T &init=T()){
  if constexpr (id<n)return vector(d[id],vec<T,n,id+1>(d,init));
  else return init;
}
#ifdef LOCAL
#include<debug.h>
#define SWITCH(a,b) (a)
#else
#define debug(...) static_cast<void>(0)
#define debugg(...) static_cast<void>(0)
#define SWITCH(a,b) (b)
template<typename T1,typename T2>ostream &operator<<(ostream &os,const pair<T1,T2>&p){os<<p.first<<' '<<p.second;return os;}
#endif
struct Timer{
  clock_t start;
  Timer(){
    start=clock();
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout<<fixed<<setprecision(16);
  }
  inline double now(){return (double)(clock()-start)/1000;}
  #ifdef LOCAL
  ~Timer(){
    cerr<<"time:";
    cerr<<now();
    cerr<<"ms\n";
  }
  #endif
}timer;
void SOLVE();
int main(){
  int testcase=1;
  //cin>>testcase;
  for(int i=0;i<testcase;i++){
    SOLVE();
  }
}
#include<type_traits>
#include<optional>
constexpr int carmichael_constexpr(int n){
  if(n==998244353)return 998244352;
  if(n==1000000007)return 1000000006;
  if(n<=1)return n;
  int res=1;
  int t=0;
  while(n%2==0){
    n/=2;
    t++;
  }
  if(t==2)res=2;
  else if(t>=3)res=1<<(t-2);
  for(int i=3;i*i<=n;i++)if(n%i==0){
    int c=0;
    while(n%i==0){
      n/=i;
      c++;
    }
    int prod=i-1;
    for(int j=0;j<c-1;j++)prod*=i;
    res=std::lcm(res,prod);
  }
  if(n!=1)res=std::lcm(res,n-1);
  return res;
}
template<int m>
struct mod_int{
private:
  static constexpr unsigned int umod=static_cast<unsigned int>(m);
  static constexpr unsigned int car=carmichael_constexpr(m);
  using uint=unsigned int;
  using mint=mod_int;
  uint v;
  static_assert(m<uint(1)<<31);
  mint sqrt_impl()const{
    if(this->val()<=1)return *this;
    if constexpr(m%8==1){
      mint b=2;
      while(b.pow((m-1)/2).val()==1)b++;
      int m2=m-1,e=0;
      while(m2%2==0)m2>>=1,e++;
      mint x=this->pow((m2-1)/2);
      mint y=(*this)*x*x;
      x*=*this;
      mint z=b.pow(m2);
      while(y.val()!=1){
        int j=0;
        mint t=y;
        while(t.val()!=1)t*=t,j++;
        z=z.pow(1<<(e-j-1));
        x*=z;
        z*=z;
        y*=z;e=j;
      }
      return x;
    }
    else if constexpr(m%8==5){
      mint ret=this->pow((m+3)/8);
      if((ret*ret).val()==this->val())return ret;
      else return ret*mint::raw(2).pow((m-1)/4);
    }
    else{
      return this->pow((m+1)/4);
    }
  }
public:
  using value_type=uint;
  mod_int():v(0){}
  template<typename T,std::enable_if_t<std::is_signed_v<T>,std::nullptr_t> =nullptr>
  mod_int(T a){
    a%=m;
    if(a<0)v=a+umod;
    else v=a;
  }
  template<typename T,std::enable_if_t<std::is_unsigned_v<T>,std::nullptr_t> =nullptr>
  mod_int(T a):v(a%umod){}
  static constexpr mint raw(int a){
    mint ret;
    ret.v=a;
    return ret;
  }
  inline uint val()const{return this->v;}
  static constexpr int mod(){return m;}
  inline mint &operator+=(const mint &b){
    this->v+=b.v;
    if(this->v>=umod)this->v-=umod;
    return *this;
  }
  inline mint &operator-=(const mint &b){
    this->v-=b.v;
    if(this->v>=umod)this->v+=umod;
    return *this;
  }
  inline mint &operator*=(const mint &b){
    this->v=((unsigned long long)this->v*b.v)%umod;
    return *this;
  }
  inline mint &operator/=(const mint &b){
    *this*=b.inv();
    return *this;
  }
  inline mint operator+()const{return *this;}
  inline mint operator-()const{return mint()-*this;}
  friend inline mint operator+(const mint &a,const mint &b){return mint(a)+=b;}
  friend inline mint operator-(const mint &a,const mint &b){return mint(a)-=b;}
  friend inline mint operator*(const mint &a,const mint &b){return mint(a)*=b;}
  friend inline mint operator/(const mint &a,const mint &b){return mint(a)/=b;}
  friend inline bool operator==(const mint &a,const mint &b){return a.val()==b.val();}
  friend inline bool operator!=(const mint &a,const mint &b){return !(a==b);}
  inline mint operator++(int){
    mint ret=*this;
    *this+=mint::raw(1);
    return ret;
  }
  inline mint operator--(int){
    mint ret=*this;
    *this-=mint::raw(1);
    return ret;
  }
  mint pow(long long n)const{
    mint ret=mint::raw(1),a(*this);
    while(n){
      if(n&1)ret*=a;
      a*=a;
      n>>=1;
    }
    return ret;
  }
  inline mint inv()const{
    assert(this->v!=0);
    return pow(car-1);
  }
  std::optional<mint>sqrt()const{
    if(this->val()<=1||this->pow((m-1)/2)==1)return std::make_optional(this->sqrt_impl());
    else return std::nullopt;
  }
  static constexpr unsigned int order(){return car;}
  friend std::istream &operator>>(std::istream &is,mint &b){
    long long a;
    is>>a;
    b=mint(a);
    return is;
  }
  friend std::ostream &operator<<(std::ostream &os,const mint &b){
    os<<b.val();
    return os;
  }
};
template<int m>
struct std::hash<mod_int<m>>{
  std::size_t operator()(mod_int<m>x)const{
    return std::hash<unsigned int>()(x.val());
  }
};
using mint998=mod_int<998244353>;
using mint107=mod_int<1000000007>;
#include<concepts>
template<typename T>
constexpr std::enable_if_t<std::numeric_limits<T>::digits<=32,int>msb(T n){return n==0?-1:31-__builtin_clz(n);}
template<typename T>
constexpr std::enable_if_t<(std::numeric_limits<T>::digits>32),int>msb(T n){return n==0?-1:63-__builtin_clzll(n);}

template<typename T>
constexpr std::enable_if_t<std::numeric_limits<T>::digits<=32,int>lsb(T n){return n==0?-1:__builtin_ctz(n);}
template<typename T>
constexpr std::enable_if_t<(std::numeric_limits<T>::digits>32),int>lsb(T n){return n==0?-1:__builtin_ctzll(n);}

template<typename T>
constexpr std::enable_if_t<std::is_integral_v<T>,T>floor_pow2(T n){return n==0?0:T(1)<<msb(n);}

template<typename T>
constexpr std::enable_if_t<std::is_integral_v<T>,T>ceil_pow2(T n){return n<=1?1:T(1)<<(msb(n-1)+1);}

template<std::integral T>
constexpr T safe_div(T a,T b){return a/b-(a%b&&(a^b)<0);}
template<std::integral T>
constexpr T safe_ceil(T a,T b){return a/b+(a%b&&(a^b)>0);}
template<typename T>
constexpr std::enable_if_t<(std::numeric_limits<T>::digits<=32),T>pow_mod(T a,T n,T mod){
  using u64=unsigned long long;
  u64 res=1;
  while(n>0){
    if(n&1)res=((u64)res*a)%mod;
    a=((u64)a*a)%mod;
    n>>=1;
  }
  return T(res);
}
template<typename T>
constexpr std::enable_if_t<(std::numeric_limits<T>::digits>32),T>pow_mod(T a,T n,T mod){
  using u128=__uint128_t;
  u128 res=1;
  while(n>0){
    if(n&1)res=((u128)res*a)%mod;
    a=((u128)a*a)%mod;
    n>>=1;
  }
  return T(res);
}
constexpr int primitive_root_constexpr(int x){
  if(x==167772161)return 3;
  if(x==469762049)return 3;
  if(x==754974721)return 11;
  if(x==880803841)return 26;
  if(x==998244353)return 3;
  if(x==2)return 1;
  int x2=x;
  int p[20]={};
  int c=0;
  x--;
  for(int i=2;i*i<=x;i++){
    if(x%i==0){
      p[c++]=i;
      while(x%i==0)x/=i;
    }
  }
  if(x!=1)p[c++]=x;
  x=x2;
  for(int g=2;;g++){
    bool ok=true;
    for(int i=0;i<c;i++)if(pow_mod(g,(x-1)/p[i],x)==1){
      ok=false;
      break;
    }
    if(ok)return g;
  }
}
template<int m>
struct ntt_root{
  static constexpr int rank2=lsb(m-1);
  static constexpr int g=primitive_root_constexpr(m);
  std::array<int,rank2+1>root,invroot;
  std::array<int,std::max(0,rank2-1)>rate2,invrate2;
  std::array<int,std::max(0,rank2-2)>rate3,invrate3;
  constexpr ntt_root(){
    root[rank2]=pow_mod(g,m>>rank2,m);
    invroot[rank2]=pow_mod(root[rank2],m-2,m);
    for(int i=rank2-1;i>=0;i--){
      root[i]=(long long)root[i+1]*root[i+1]%m;
      invroot[i]=(long long)invroot[i+1]*invroot[i+1]%m;
    }
    int prod=1,invprod=1;
    for(int i=0;i<rank2-1;i++){
      rate2[i]=(long long)root[i+2]*prod%m;
      invrate2[i]=(long long)invroot[i+2]*invprod%m;
      prod=(long long)prod*invroot[i+2]%m;
      invprod=(long long)invprod*root[i+2]%m;
    }
    prod=invprod=1;
    for(int i=0;i<rank2-2;i++){
      rate3[i]=(long long)root[i+3]*prod%m;
      invrate3[i]=(long long)invroot[i+3]*invprod%m;
      prod=(long long)prod*invroot[i+3]%m;
      invprod=(long long)invprod*root[i+3]%m;
    }
  }
};
template<typename T>
void dft(std::vector<T>&a){
  static constexpr ntt_root<T::mod()>r;
  static constexpr unsigned long long mod2=(unsigned long long)T::mod()*T::mod();
  int n=a.size();
  int h=lsb(n);
  int len=0;
  while(len<h){
    if(h-len==1){
      T rot=T::raw(1);
      for(int s=0;s<(1<<len);s++){
        int of=s*2;
        T u=a[of],v=a[of+1]*rot;
        a[of]=u+v;
        a[of+1]=u-v;
        rot*=T::raw(r.rate2[lsb(~(unsigned int)s)]);
      }
      len++;
    }
    else{
      int p=1<<(h-len-2);
      T rot=T::raw(1),imag=T::raw(r.root[2]);
      for(int s=0;s<(1<<len);s++){
        const unsigned long long rot1=rot.val(),rot2=rot1*rot1%T::mod(),rot3=rot1*rot2%T::mod();
        int of=s<<(h-len);
        for(int i=0;i<p;i++){
          const unsigned long long a0=a[i+of].val(),a1=(unsigned long long)a[i+of+p].val()*rot1,a2=(unsigned long long)a[i+of+p*2].val()*rot2,a3=(unsigned long long)a[i+of+p*3].val()*rot3;
          const unsigned long long m=(unsigned long long)T(a1+mod2-a3).val()*imag.val();
          const unsigned long long k=mod2-a2;
          a[i+of]=a0+a2+a1+a3;
          a[i+of+p]=a0+a2+(mod2*2-a1-a3);
          a[i+of+p*2]=a0+k+m;
          a[i+of+p*3]=a0+k+(mod2-m);
        }
        rot*=T::raw(r.rate3[lsb(~(unsigned int)s)]);
      }
      len+=2;
    }
  }
}
template<typename T>
void idft(std::vector<T>&a){
  static constexpr ntt_root<T::mod()>r;
  int n=a.size();
  int h=lsb(n);
  int len=h;
  while(len){
    if(len==1){
      int p=1<<(h-1);
      for(int i=0;i<p;i++){
        T u=a[i],v=a[i+p];
        a[i]=u+v;
        a[i+p]=u-v;
      }
      len--;
    }
    else{
      int p=1<<(h-len);
      T rot=T::raw(1),imag=T::raw(r.invroot[2]);
      for(int s=0;s<(1<<(len-2));s++){
        const unsigned long long rot1=rot.val(),rot2=rot1*rot1%T::mod(),rot3=rot1*rot2%T::mod();
        int of=s<<(h-len+2);
        for(int i=0;i<p;i++){
          const unsigned long long a0=a[i+of].val(),a1=a[i+of+p].val(),a2=a[i+of+p*2].val(),a3=a[i+of+p*3].val();
          const unsigned long long k=T((T::mod()+a2-a3)*imag.val()).val();
          a[i+of]=a0+a1+a2+a3;
          a[i+of+p]=(a0+T::mod()-a1+k)*rot1;
          a[i+of+p*2]=(a0+a1+T::mod()*2-a2-a3)*rot2;
          a[i+of+p*3]=(a0+T::mod()*2-a1-k)*rot3;
        }
        rot*=T::raw(r.invrate3[lsb(~(unsigned int)s)]);
      }
      len-=2;
    }
  }
}
template<typename T>
std::vector<T>ntt_convolution(std::vector<T> a,std::vector<T> b){
  int n=a.size(),m=b.size(),s=n+m-1;
  if(std::min(n,m)<60){
    std::vector<T>ret(s,0);
    if(n<m)for(int i=0;i<m;i++)for(int j=0;j<n;j++)ret[i+j]+=a[j]*b[i];
    else for(int i=0;i<n;i++)for(int j=0;j<m;j++)ret[i+j]+=a[i]*b[j];
    return ret;
  }
  int z=ceil_pow2(s);
  a.resize(z,0);
  b.resize(z,0);
  dft(a),dft(b);
  std::vector<T>c(z);
  for(int i=0;i<z;i++)c[i]=a[i]*b[i];
  idft(c);
  T g=T::raw(z).inv();
  for(int i=0;i<s;i++)c[i]*=g;
  return {c.begin(),c.begin()+s};
}
#include<initializer_list>
struct is_modint_impl{
  template<typename T>
  static auto check(T&&x)->decltype(x.mod(),std::true_type{});
  template<typename T>
  static auto check(...)->std::false_type;
};
template<typename T>
struct is_modint:public decltype(is_modint_impl::check<T>(std::declval<T>())){};
template<typename T>
inline constexpr bool is_modint_v=is_modint<T>::value;
struct is_dynamic_modint_impl{
  template<typename T>
  static auto check(T&&x)->decltype(x.set_mod((typename T::value_type)0),std::true_type{});
  template<typename T>
  static auto check(...)->std::false_type;
};
template<typename T>
struct is_dynamic_modint:public decltype(is_dynamic_modint_impl::check<T>(std::declval<T>())){};
template<typename T>
inline constexpr bool is_dynamic_modint_v=is_dynamic_modint<T>::value;
template<typename T>
inline constexpr bool is_static_modint_v=is_modint_v<T>&&!is_dynamic_modint_v<T>;
struct is_uso_modint_impl{
  template<typename T>
  static auto check(T&&x)->decltype(x.uso(),std::true_type{});
  template<typename T>
  static auto check(...)->std::false_type;
};
template<typename T>
struct is_uso_modint:public decltype(is_uso_modint_impl::check<T>(std::declval<T>())){};
template<typename T>
inline constexpr bool is_uso_modint_v=is_uso_modint<T>::value;
template<typename T>
struct F{
private:
  static int capacity;
  static std::vector<T>fact,factinv,inv;
public:
  static void resize(int n){
    if(capacity>=n)return;
    fact.resize(n+1),factinv.resize(n+1),inv.resize(n+1);
    for(int i=capacity+1;i<=n;i++){
      fact[i]=fact[i-1]*T::raw(i);
      if constexpr(is_uso_modint_v<T>)inv[i]=T(1)/T(i);
      else inv[i]=-inv[T::mod()%i]*(T::mod()/i);
      factinv[i]=factinv[i-1]*inv[i];
    }
    capacity=n;
  }
  static T C(int n,int k){
    if(n<k)return 0;
    if(k<0)return 0;
    resize(n);
    return fact[n]*factinv[k]*factinv[n-k];
  }
  static T P(int n,int k){
    if(n<k)return 0;
    if(k<0)return 0;
    resize(n);
    return fact[n]*factinv[n-k];
  }
  static T H(int n,int k){
    if(n==0&&k==0)return 1;
    return C(n+k-1,k);
  }
  static T factorial(int n){
    resize(n);
    return fact[n];
  }
  static T factorial_inv(int n){
    resize(n);
    return factinv[n];
  }
  static T inverse(int n){
    resize(n);
    return inv[n];
  }
  static T S(long long n,int k){
    if(n<0)return 0;
    if(n<k)return 0;
    T ret=0;
    resize(k);
    for(int i=0;i<=k;i++){
      ret+=fact[k]*factinv[i]*factinv[k-i]*T::raw(i).pow(n)*((k-i)&1?-1:1);
    }
    return ret*factinv[k];
  }
  template<typename... INT>
  static T O(INT...k){
    int n=0;
    for(int i:std::initializer_list<int>{k...}){
      if(i<0)return 0;
      n+=i;
    }
    resize(n);
    T ret=fact[n];
    for(int i:std::initializer_list<int>{k...})ret*=factinv[i];
    return ret;
  }
};
template<typename T>int F<T>::capacity=1;
template<typename T>std::vector<T>F<T>::fact{1,1};
template<typename T>std::vector<T>F<T>::factinv{1,1};
template<typename T>std::vector<T>F<T>::inv{0,1};
//lower[i]<=A[i]<=upper[i]
template<typename T>
T counting_increasing_sequence(std::vector<int>lower,std::vector<int>upper){
  assert(lower.size()==upper.size());
  int n=lower.size();
  for(int i=1;i<n;i++)if(lower[i-1]>lower[i])lower[i]=lower[i-1];
  for(int i=n-2;i>=0;i--)if(upper[i]>upper[i+1])upper[i]=upper[i+1];
  for(int i=0;i<n;i++)if(lower[i]>upper[i])return 0;
  int f=lower[0];
  for(int i=0;i<n;i++){
    lower[i]-=f;
    upper[i]-=f;
  }
  lower.insert(lower.begin(),0);
  upper.push_back(upper.back());
  int m=upper[n];
  std::vector<T>red(n+1),blue(m+1);
  //下限同じ、上限単調増加(愚直)
  auto naive1=[&](int lx,int rx,int ly,int ry)->void {
    std::vector<std::vector<T>>dp(rx-lx+1,std::vector<T>(ry-ly+1,0));
    for(int i=lx;i<=rx;i++)dp[i-lx][0]=red[i];
    for(int j=ly+1;j<=upper[lx];j++)dp[0][j-ly]=dp[0][j-ly-1];
    for(int i=lx+1;i<=rx;i++){
      for(int j=ly+1;j<=upper[i];j++)dp[i-lx][j-ly]=dp[i-lx-1][j-ly]+dp[i-lx][j-ly-1];
    }
    for(int j=ly;j<=ry;j++)blue[j]=dp.back()[j-ly];
  };
  //下限単調増加、上限同じ(愚直)
  auto naive2=[&](int lx,int rx,int ly,int ry)->void {
    std::vector<std::vector<T>>dp(rx-lx+1,std::vector<T>(ry-ly+1,0));
    for(int j=ly;j<=ry;j++)dp[0][j-ly]=blue[j];
    for(int i=lx+1;i<=rx;i++){
      dp[i-lx][lower[i]-ly]=dp[i-lx-1][lower[i]-ly];
      for(int j=lower[i]+1;j<=ry;j++){
        dp[i-lx][j-ly]=dp[i-lx-1][j-ly]+dp[i-lx][j-ly-1];
      }
    }
    for(int i=lx;i<=rx;i++)red[i]=dp[i-lx].back();
  };
  auto calc_naive=[&](int lx,int rx,int ly,int ry)->void {
    std::vector<std::vector<T>>dp(rx-lx+1,std::vector<T>(ry-ly+1,0));
    for(int i=lx;i<=rx;i++)dp[i-lx][0]=red[i];
    for(int i=ly;i<=ry;i++)dp[0][i-ly]=blue[i];
    for(int i=1;i<=rx-lx;i++)for(int j=1;j<=ry-ly;j++){
      dp[i][j]=dp[i-1][j]+dp[i][j-1];
    }
    for(int i=lx;i<=rx;i++)red[i]=dp[i-lx][ry-ly];
    for(int i=ly;i<=ry;i++)blue[i]=dp[rx-lx][i-ly];
  };
  //長方形の寄与を畳み込みで計算
  auto calc=[&](int lx,int rx,int ly,int ry){
    std::vector<T>l(blue.begin()+ly,blue.begin()+ry+1);
    std::vector<T>d(red.begin()+lx,red.begin()+rx+1);
    for(int i=lx;i<=rx;i++)red[i]=0;
    for(int i=ly;i<=ry;i++)blue[i]=0;
    int x=rx-lx,y=ry-ly;
    for(int i=x;i>=1;i--)d[i]-=d[i-1];
    for(int i=y;i>=1;i--)l[i]-=l[i-1];
    int s=ceil_pow2(x+y+2);
    T invs=T(s).inv();
    d[0]=0;
    {//下から上
      vector<T>coef(x+1);
      for(int i=0;i<=x;i++)coef[i]=F<T>::C(y+i,i);
      coef=ntt_convolution(coef,d);
      for(int i=0;i<=x;i++)red[i+lx]+=coef[i];
    }
    {//左から右
      vector<T>coef(y+1);
      for(int i=0;i<=y;i++)coef[i]=F<T>::C(x+i,i);
      coef=ntt_convolution(coef,l);
      for(int i=0;i<=y;i++)blue[i+ly]+=coef[i];
    }
    vector<T>coef(s,0);
    for(int i=0;i<=x+y;i++)coef[i]=F<T>::factorial(i);
    dft(coef);
    {//下から右
      for(int i=0;i<=x;i++)d[i]*=F<T>::factorial_inv(x-i);
      d.resize(s,0);
      dft(d);
      for(int i=0;i<s;i++)d[i]*=coef[i];
      idft(d);
      for(int i=0;i<=y;i++)blue[i+ly]+=d[i+x]*F<T>::factorial_inv(i)*invs;
    }
    {//左から上
      for(int i=0;i<=y;i++)l[i]*=F<T>::factorial_inv(y-i);
      l.resize(s,0);
      dft(l);
      for(int i=0;i<s;i++)l[i]*=coef[i];
      idft(l);
      for(int i=0;i<=x;i++)red[i+lx]+=l[i+y]*F<T>::factorial_inv(i)*invs;
    }
  };
  //下限同じ、上限単調増加(分割統治)
  auto dfs1=[&](auto self,int lx,int rx,int ly,int ry)->void {
    if((long long)(rx-lx)*(ry-ly)<=150){
      naive1(lx,rx,ly,ry);
      return;
    }
    int mid=-1;
    long long s=0;
    for(int i=lx;i<=rx;i++){
      long long now=(long long)(rx-i)*(upper[i]-ly);
      if(s<now)mid=i,s=now;
    }
    if(mid==-1){
      for(int i=ly;i<=ry;i++)blue[i]=red[rx];
      return;
    }
    int y=upper[mid];
    self(self,lx,mid,ly,y);
    red[mid]=blue[ly];
    calc(mid,rx,ly,y);
    self(self,mid,rx,y,ry);
  };
  //下限単調増加、上限同じ(分割統治)
  auto dfs2=[&](auto self,int lx,int rx,int ly,int ry)->void {
    if((long long)(rx-lx)*(ry-ly)<=150){
      naive2(lx,rx,ly,ry);
      return;
    }
    int mid=-1;
    long long s=0;
    for(int i=lx;i<=rx;i++){
      long long now=(long long)(i-lx)*(ry-lower[i]);
      if(s<now)mid=i,s=now;
    }
    if(mid==-1){
      for(int i=lx;i<=rx;i++)red[i]=blue[ry];
      return;
    }
    int y=lower[mid];
    self(self,lx,mid,ly,y);
    blue[y]=red[lx];
    calc(lx,mid,y,ry);
    self(self,mid,rx,y,ry);
  };
  int x=0,y=0;
  red[0]=1;
  while(x<n&&lower[x+1]==y)red[x+1]=red[x],x++;
  int lx=0,ly=0;
  while(true){
    ly=y;
    y=upper[x];
    dfs1(dfs1,lx,x,ly,y);
    if(x==n)break;
    lx=x;
    while(x<n&&lower[x+1]<=y)x++;
    dfs2(dfs2,lx,x,ly,y);
  }
  return blue.back();
}
using mint=mint998;
mint solve(int n,int k){
  if(k==0)return 0;
  vector<int>l(n),r(n);
  rep(i,n){
    l[i]=max(0,i-k+1);
    r[i]=i;
  }
  return counting_increasing_sequence<mint>(l,r);
}
void SOLVE(){
  int n,k;
  cin>>n>>k;
  cout<<solve(n,k)-solve(n,k-1)<<endl;
}
0