#include <fstream>

using namespace std;


ifstream fin("fractal.in");
ofstream fout("fractal.out");

int n,x,y,lat;

int cer(int lat, int x, int y)
{
    if (lat==1)
        return 0;

    lat/=2;
    if (x<=lat && y<=lat)
        return cer(lat,y,x);

    if (x<=lat)
        return lat*lat+cer(lat,x,y-lat);

    if (y<=lat)
        return 3*lat*lat+cer(lat,lat-y+1,2*lat-x+1);

    return 2*lat*lat+cer(lat,x-lat,y-lat);
}

int main()
{
    fin>>n>>x>>y;
    lat=1<<n;
    fout<<cer(lat,x,y);

    return 0;
}