Stars and Arrows

The environment enables the user to typeset 'Stars and Arrows' logic puzzles (aka Sternenhimmel, ...)
Enter a star in some empty cells of the grid. Each arrow points to at least one star and every star is referenced by at least one arrow. Arrows point to a whole row, column or diagonal, also through other stars and arrows. The numbers on the left and top of the grid indicate how many stars are located in the row or column.

\begin{center}
  \begin{starsandarrows}
    \framepuzzle
    \starsH{1,2,3,2,0}
    \starsV{1,0,3,2,2}
    \setrow{5}{\RightDown,{},\LeftDown}
    \setrow{4}{{},\Right,{},{},\LeftUp}
    \setrow{2}{{},\Up,{},{},{}}
    \setrow{1}{\RightUp,{},{},\LeftUp,\Left}
  \end{starsandarrows}
  \hspace{1.5cm}
  \begin{starsandarrows}
    \framepuzzle
    \starsH{1,2,3,2,0}
    \starsV{1,0,3,2,2}
    \setrow{5}{\RightDown,\Star,\LeftDown,\Star}
    \setrow{4}{{},\Right,\Star,\Star,\LeftUp}
    \setrow{3}{\Star,\Star,\Star}
    \setrow{2}{{},\Up,{},{},{}}
    \setrow{1}{\RightUp,{},\Star,\LeftUp,\Left}
  \end{starsandarrows}
\end{center}