#include <iostream>
#include<fstream>
using namespace std;
int x,y,k,sum,nr;

int main()
{
    ifstream f("fractal.in");
    ofstream g("fractal.out");
    f>>k>>x>>y;
    nr=(1<<(k-1));
    while(nr>=1)
{


    if(x>nr)
    {
        x-=nr;
        if(y<=nr){sum+=3*nr*nr;}
          else {sum+=2*nr*nr;y-=nr;}
    }
    else
    {
        if(y>nr) {sum+=nr*nr;y-=nr;}

    }


    nr/=2;
}
g<<sum;

    return 0;
}