GG

#include <iostream>
#define LD long double
using namespace std;
LD Comb(int n,int m)
{
    LD cnk=1;
    int i=0;
    for(int k=1;k<=m;++k)
    {
        cnk=cnk*(n-k+1)/k;
        while(cnk>=1&&i<n)
            cnk/=2,++i;
    }
    for(int k=i+1;k<=n;++k)
        cnk/=2;
    return cnk;
}
int main()
{
    int n,m;
    cin>>n>>m;
    cout<<Comb(n+m-2,n-1);
    return 0;
}