#include #include using namespace std; using namespace atcoder; typedef long long int ll; typedef long double ld; #define FOR(i,l,r) for(ll i=l;i=l;i--) #define RREP(i,n) RFOR(i,0,n) #define ALL(x) x.begin(),x.end() #define PA pair #define F first #define S second #define BS(A,x) binary_search(ALL(A),x) #define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin()) #define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin()) #define COU(A,x) (UB(A,x)-LB(A,x)) #define sz(c) ((ll)(c).size()) /* #include namespace mp=boost::multiprecision; using Bint=mp::cpp_int; */ templateusing min_priority_queue=priority_queue,greater>; templateostream&operator<<(ostream&os,pair&p){os<istream&operator>>(istream&is,pair&p){is>>p.F>>p.S;return is;} templateostream&operator<<(ostream&os,vector&v){REP(i,sz(v))os<istream&operator>>(istream&is,vector&v){for(T&in:v)is>>in;return is;} templatebool chmax(T&a,T b){if(abool chmin(T&a,T b){if(bfast_mod_convolution(vector&a,vector&b,ll mod){ const ll m1=167772161,m2=469762049,m3=1224736769; const ll m1_inv_m2=inv_mod(m1,m2); const ll m12_inv_m3=inv_mod(m1*m2,m3); const ll m12_mod=m1*m2%mod; auto x=convolution(a,b); auto y=convolution(a,b); auto z=convolution(a,b); vectorret(sz(a)+1); REP(i,sz(a)+1){ ll v1=(y[i]-x[i])*m1_inv_m2%m2;if(v1<0)v1+=m2; ll v2=(z[i]-(x[i]+m1*v1)%m3)*m12_inv_m3%m3;if(v2<0)v2+=m3; ret[i]=(x[i]+m1*v1+m12_mod*v2)%mod; } return ret; } int main(){ ll N,K;cin>>N>>K; mint ans=0,t=1; REP(i,N)t*=K-i+max(0LL,N-K); vectorex(N,1),r(N); FOR(i,1,N)ex[i]=i*ex[i-1]; REP(i,N)r[i]=1/ex[i]; FOR(i,max(0LL,N-K),N){ ans+=t*r[i]*r[N-1-i]; t=t/(K-N+1+i)*(K+1+i); } ans/=N; cout<