How to labelOnlyAB in venndiagram2sets?

Question

I am trying to labelOnlyAB={9} in this code, but I cannot result.

\documentclass{article}
\usepackage{venndiagram}
\begin{document}
\begin{venndiagram2sets}[labelOnlyA={18},labelOnlyB={24},
    labelOnlyAB={9},
    labelNotAB={45}]
\end{venndiagram2sets}
\end{document}

How can I get the result?

Answer 1

You should use labelAB={9} instead of using labelOnlyAB={9}.

\documentclass{article}
\usepackage{venndiagram}
\begin{document}
    \begin{venndiagram2sets}[labelOnlyA={18},labelOnlyB={24},
        labelAB={9},
        labelNotAB={45}]
    \end{venndiagram2sets}
\end{document}

Answer 2

For fun with Asymptote.

// http://asymptote.ualberta.ca/
unitsize(1.5cm);
real d=.6;
transform t=shift(d,0), s=inverse(t);
draw(tunitcircle,blue);
draw(sunitcircle,magenta);
label(t"24",E); label("B",t(0,1),S);
label(s"18",W); label("A",s(0,1),S);
real a=2.2,b=1.3;
draw(box((-a,-b),(a,b)));
label("45",align=3NE,(-a,-b));
shipout(bbox(5mm,invisible));