program fractal;
type ta=array [0..20] of longint;


var f:text;
    p,n,x,y,i:longint;
    a:ta;




function calcul(k,x,y:longint):longint;
begin
if p>1 then
   begin
   p:=p div 2;
   if (y>p) and (x<=p) then calcul:=a[k-1]+1+calcul(k-1,x,y-p);
   if (y>p) and (x>p) then calcul:=2*a[k-1]+2+calcul(k-1,x-p,y-p);
   if (y<=p) and (x<=p) then calcul:=calcul(k-1,y,x);
   if (y<=p) and (x>p) then calcul:=3*a[k-1]+3+calcul(k-1,p-y+1,p*2-x+1);
   end
   else
   calcul:=0;
end;







begin
assign(f,'fractal.in');reset(f);
read(f,n,x,y);
close(f);
a[0]:=0;
for i:=1 to n do
    a[i]:=a[i-1]*4+3;
p:=1;
for i:=1 to n do
    p:=p*2;
assign(f,'fractal.out');rewrite(f);
write(f,calcul(n,x,y));
close(f);
end.