//Fractal 2008

#include <fstream>
using namespace std;
ifstream fin("fractal.in");
ofstream fout("fractal.out");

int fractal(int x,int y,int p){
    int fract=0;
    if ((x==y&&x==1)||p==1) return 0;
    else
        if (x<=p/2){
                if (y<=p/2){
                        fract=fractal(y,p/2-x,p/2);
                        return fract;
                }
                if (y>p/2){
                        fract=fractal(x,y-p/2,p/2);
                        return (p/2)*(p/2)+fract;
                }
        }  else
                {
                if (y>p/2)
                {
                        fract=fractal(x-p/2,y-p/2,p/2);
                        return 2*(p/2)*(p/2)+fract;
                }
                if (y<=p/2)
                {
                        fract=fractal(p/2-y+1,p-x+1,p/2);
                        return 3*(p/2)*(p/2)+fract;
                }
        }
}
int main(){
    int x,y,p,k;
    fin>>k>>x>>y;
    p=1<<k;
    fout<<fractal(x,y,p);
    fout.close();
    return 0;
}