#include <math.h>
#include <iostream.h>
#include <fstream.h>

int fractal(int k,int x,int y)
{
	if(x==1 && y==1) return 0;
	else if(x==1 && y==2) return 1;
	else if(x==2 && y==1) return 2;
	else if(x==2 && y==2) return 3;
	else
	{
		int putere=pow(2,k);
		if(x<=putere/2 && y<=putere/2)
			return putere/2*putere/2-fractal(k-1,putere/2-y+1,x);
		else if(x<=putere/2 && y>putere/2)
			return putere/2*putere/2-1+fractal(k-1,x,y-putere/2);
		else if(x>putere/2 && y>putere/2)
			return putere*putere/2-1 +fractal(k-1,x-putere/2,y-putere/2);
		else return 3*putere/2*putere/2-1 -fractal(k-1,y,putere-x+1) + putere/2*putere/2;
	}
}
int main()
{
	ifstream f("fractal.in");
	ofstream g("fractal.out");
	int k,x,y;
	f>>k>>x>>y;
	int result=fractal(k,x,y);
	g<<result;
	f.close();
	g.close();
	return 0;
}