#include <fstream>

using namespace std;
ifstream in("fractal.in");
ofstream out("fractal.out");
int sol=0;
void rez(int k, int x, int y)
{
    if(k==0)
        return;
    int put;
    put=(1<<(k-1));
    if(x<=put&&y<=put)
    {
        rez(k-1,y,x);
    }
    else
    if(x>put&&y<=put)
    {
        sol+=put*put;
        rez(k-1,x-put,y);
    }
    else
    if(x>put&&y>put)
    {
        sol+=2*put*put;
        rez(k-1,x-put,y-put);
    }
    else
    if(x<=put&&y>put)
    {
        sol+=3*put*put;
        rez(k-1,put-(y-put)+1,put-x+1);
    }

}



int main()
{
    int x,y,k;
    in>>k>>x>>y;
    rez(k,y,x);
    out<<sol<<'\n';
    return 0;
}