#include <fstream>
#include <iomanip>
#include <math.h>
using namespace std;
ifstream f("fractal.in");
ofstream g("fractal.out");
int solvation(int a, int b, int c)
{
	if (a==0) 
		return 0;
	if ((b>a)&&(c<=a)) 
		return a*a+solvation(a/2, b-a, c);
	if ((b<=a)&&(c>a))
		return 3*a*a+solvation(a/2, 2*a-c+1, a-b+1);
	if ((b<=a)&&(c<=a))
		return solvation(a/2, c, b);
	if ((b>a)&&(c>a))  
		return 2*a*a+solvation(a/2, b-a, c-a);
}
int i;
int n,x,y;
int main()
{
	int k=1;
	f>>n>>x>>y;
	for (i=1;i<=n-1;i++)
		k*=2;
	int rez=solvation(k,x,y);
	g<<rez;
  return 0;
}