#include <fstream>
using namespace std;
ifstream fin("fractal.in");
ofstream fout("fractal.out");
int x,k,y,l,z,i,j;
int main()
{
    fin>>k>>x>>y;
    while(k){
        --k,z=(1<<k);
        if(x>z)
            if(y>z)
                l=l+2*z*z,x-=z,y-=z;
            else
                l=l+3*z*z,x-=z,j=x,x=z-y+1,y=z-j+1;
        else if(y>z)
            l=l+z*z,y-=z;
        else
            i=x,x=y,y=i;
    }
    fout<<l<<"\n";
    fin.close();
    fout.close();
    return 0;
}