#include<iostream>

#include<cstdio>

#include<cstring>

#define N 200001

#define M 1000000007

#define ll long long

using namespace std;

ll fac[N]={,},inv[N]={,},f[N]={,};

int n,m;

ll C(ll a,ll b)

{

    return fac[a]*inv[b]%M*inv[a-b]%M;

}

int main()

{

    for(int i=;i<N;i++)

    {

        fac[i]=fac[i-]*i%M;

        f[i]=(M-M/i)*f[M%i]%M;

        inv[i]=inv[i-]*f[i]%M;

    }

    while(~scanf("%d%d",&n,&m)) printf("%lld\n",C(m+n-,m-));

    return ;

}