program wto;
var
a,b,s,c:double ;
best:longint;
begin
assign(input,'ring.in');
reset(input);
assign(output,'ring.out');
rewrite(output);
read(a,b);
s:=a*1.0/(2*b);
c:=trunc(s)+0.5;
if abs(s-c)<0.000001 then begin writeln('0');exit;end
else
if s<c then best:=trunc(s)
else best:=trunc(s)+1;
if (0.3*sqrt(a*best-b*best))<0 then writeln('0')
else writeln(best);
close(input);
close(output);
end.