  Let $g=(g_{ij})$ be a complete Riemmanian metric on $\R^2$ with finite total
area and $I_g=\inf_{\gamma}I(\gamma)$ with
$I(\gamma)=L(\gamma)(A_{in}(\gamma)^{-1}+A_{out}(\gamma)^{-1})$ where $\gamma$
is any closed simple curve in $\R^2$, $L(\gamma)$ is the length of $\gamma$,
$A_{in}(\gamma)$ and $A_{out}(\gamma)$ are the area of the regions inside and
outside $\gamma$ respectively, with respect to the metric $g$. We prove the
existence of a minimizer for $I_g$. As a corollary we obtain a new proof for
the existence of a minimizer for $I_{g(t)}$ for any $0<t<T$ when the metric
$g(t)=g_{ij}(\cdot,t)=u\delta_{ij}$ is the maximal solution of the Ricci flow
equation $\1 g_{ij}/\1 t=-2R_{ij}$ on $\R^2\times (0,T)$ \cite{DH} where $T>0$
is the extinction time of the solution.
