#include <cstdio>
using namespace std;
int x,y,k;
FILE*f=freopen("fractal.in","r",stdin);
FILE*g=freopen("fractal.out","w",stdout);

int divide(int k,int x,int y)
{   if(k==1) return 0;
    k/=2;
    if(x<=k&&y<=k) return divide(k,y,x);
    if(x<=k)       return k*k+divide(k,x,y-k);
    if(y<=k)       return k*k*3+divide(k,k-y+1,2*k-x+1);
                   return k*k*2+divide(k,x-k,y-k);
}

int main()
{scanf("%d %d %d",&k,&x,&y);
 printf("%d",divide(1<<k,x,y));
}