/**************************************************************    Problem: 3907    User: BeiYu    Language: C++    Result: Accepted    Time:108 ms    Memory:1580 kb****************************************************************/ #include<cstdio>#include<cmath>#include<vector>#include<algorithm>#include<iostream>using namespace std; typedef long long LL;const int B = 10;const int W = 1; struct Big{    vector<int> s;    void clear(){ s.clear(); }         Big(LL num=0){ *this=num; }    Big operator = (LL x){        clear();        do{ s.push_back(x%B),x/=B; }while(x);        return *this;    }    Big operator = (const string &str){        clear();        int x,len=(str.length()-1)/W+1,l=str.length();        for(int i=0;i<len;i++){            int tt=l-i*W,st=max(0,tt-W);            sscanf(str.substr(st,tt-st).c_str(),"%d",&x);            s.push_back(x);        }return *this;//      clear();reverse(str.begin(),str.end());//      int x,len=(str.length()-1)/W+1,l=str.length();//      for(int i=0;i<len;i++){//          int st=i,tt=min(i+W,l);//          sscanf(str.substr(st,tt-st).c_str(),"%d",&x);//          s.push_back(x);//      }return *this;    }//  Big operator = (char *str){//      clear();reverse(str.begin(),str.end());//      int x,len=(str.length()-1)/W+1,l=str.length();//      for(int i=0;i<len;i+=W){//          int s=i,t=min(i+W,l);//          sscanf(str(s,t-s),"%d",&x);//          s.push_back(x);//      }return *this;//  }}; istream& operator >> (istream & in,Big &a){    string s;    if(!(in>>s)) return in;    a=s;return in;} ostream& operator << (ostream &out,const Big &a){    cout<<a.s.back();    for(int i=a.s.size()-2;~i;i--){        cout.width(W),cout.fill(‘0‘),cout<<a.s[i];    }return out;} bool operator < (const Big &a,const Big &b){    int la=a.s.size(),lb=b.s.size();    if(la<lb) return 1;if(la>lb) return 0;    for(int i=la-1;~i;i--){        if(a.s[i]<b.s[i]) return 1;        if(a.s[i]>b.s[i]) return 0;    }return 0;}bool operator <= (const Big &a,const Big &b){ return !(b<a); }bool operator > (const Big &a,const Big &b){ return b<a; }bool operator >= (const Big &a,const Big &b){ return !(a<b); }bool operator == (const Big &a,const Big &b){ return !(a>b) && !(a<b); }bool operator != (const Big &a,const Big &b){ return a>b || a<b ; }  Big operator + (const Big &a,const Big &b){    Big c;c.clear();    int lim=max(a.s.size(),b.s.size()),la=a.s.size(),lb=b.s.size(),i,g,x;    for(i=0,g=0;;i++){        if(g==0 && i>=lim) break;        x=g;if(i<la) x+=a.s[i];if(i<lb) x+=b.s[i];        c.s.push_back(x%B),g=x/B;    }i=c.s.size()-1;    while(c.s[i]==0 && i) c.s.pop_back(),i--;    return c;}Big operator - (const Big &a,const Big &b){    Big c;c.clear();    int i,g,x,la=a.s.size(),lb=b.s.size();    for(i=0,g=0;i<la;i++){        x=a.s[i]-g;        if(i<lb) x-=b.s[i];        if(x>=0) g=0;else g=1,x+=B;        c.s.push_back(x);    }i=c.s.size()-1;    while(c.s[i]==0 && i) c.s.pop_back(),i--;    return c;}Big operator * (const Big &a,const Big &b){    Big c;    int i,j,la=a.s.size(),lb=b.s.size(),lc=la+lb;    c.s.resize(lc,0);    for(i=0;i<la;i++) for(j=0;j<lb;j++) c.s[i+j]+=a.s[i]*b.s[j];    for(i=0;i<lc;i++) c.s[i+1]+=c.s[i]/B,c.s[i]%=B;    i=lc-1;while(c.s[i]==0 && i) c.s.pop_back(),i--;    return c;}Big operator / (const Big &a,const Big &b){    Big c,f=0;    int la=a.s.size(),i;    c.s.resize(la,0);    for(i=la-1;~i;i--){        f=f*B,f.s[0]=a.s[i];        while(f>=b) f=f-b,c.s[i]++;    }i=la-1;while(c.s[i]==0 && i) c.s.pop_back(),i--;    return c;}Big operator % (const Big &a,const Big &b){    Big c=a-(a/b)*b;    return c;}Big operator ^ (Big &a,Big &b){    Big c=1;    for(;b!=0;b=b/2,a=a*a){        if(b.s[0] & 1) c=c*a;    }return c;}Big operator += (Big &a,const Big &b){ return a=a+b; }Big operator -= (Big &a,const Big &b){ return a=a-b; }Big operator *= (Big &a,const Big &b){ return a=a*b; }Big operator /= (Big &a,const Big &b){ return a=a/b; }Big operator %= (Big &a,const Big &b){ return a=a%b; } const int N = 10005; int cnt;int b[N],pr[N],minp[N],c[N]; void Pre(int t){    minp[1]=0;    for(int i=2;i<=t;i++){        if(!b[i]) pr[++cnt]=i,minp[i]=cnt;        for(int j=1;j<=cnt && i*pr[j]<=t;j++){            b[i*pr[j]]=1,minp[i*pr[j]]=j;            if(i%pr[j]==0) break;        }    }}void Add(int x,int v){ while(x>1) c[minp[x]]+=v,x/=pr[minp[x]]; }int main(){    ios::sync_with_stdio(false);//  cout<<"qwq"<<endl;    int n,m;Big a=1,b,d;    cin>>n>>m;    Pre(n+m);//  cout<<"qwq"<<endl;//  cout<<cnt<<endl;//  for(int i=1;i<=cnt;i++) cout<<pr[i]<<" ";cout<<endl;         for(int i=n+2;i<=n+m;i++) Add(i,1);    Add(n-m+1,1);    for(int i=1;i<=m;i++) Add(i,-1);         for(int i=1;i<=cnt;i++){        b=pr[i],d=c[i],a*=b^d;//      cout<<b;cout<<" ";cout<<d;cout<<" ";cout<<(b^d);cout<<endl;    }    cout<<a<<endl;    return 0;}