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.