#include <fstream>
#include <deque>

using namespace std;

ifstream f("pm.in");
ofstream g("pm.out");

deque<int> operator+(deque<int> d1,deque<int> d2){
    deque<int> s;
    int ax=0;
    for(unsigned i=0;i<d1.size()||i<d2.size()||ax;i++,ax/=10){
        if(i<d1.size()) ax+=d1[i];
        if(i<d2.size()) ax+=d2[i];
        s.push_back(ax%10);
    }
    return s;
}

int main()
{
    int x,y;

    f>>x>>y;
    x++;

    deque<int> dq[2][252];
    for(int i=1;i<=x;i++)
        dq[0][i].push_back(1);

    int t=0;

    for(int i=1;i<=y;i++){
        t^=1;
        dq[t][i].clear();
        dq[t][i].push_back(1);
        for(int j=i+1;j<=x;j++)
            dq[t][j]=dq[t][j-1]+dq[t^1][j-1];
    }

    for(int i=dq[y%2][x].size()-1;i>=0;i--)
        g<<dq[y%2][x][i];


    return 0;
}