%flow.fg5:
\centerline{\kern.2\hsize \hsize=.87\hsize
\flowchart{\flowstartcircle1
\flowdecide NY{}{skip?}\flowendmiddlepart
\flowleftpart\flowdecide Y{}N{last atom?}
\flowmark0\flowmark0\flowmark0\flowmark0
\flowdecide{}YN{first coordinate?}
\flowmark0\flowmark0\flowendmiddlepart
\flowrightpart\flowdecide~~{}{case 1 or 2?}
\flowendmiddlepart\flowrightpart
\flowcompute{case 2}\flowendrightpart
\flowleftpart\flowcompute{case 1}
\flowendleftpart\flowcombine
\flowcompute{cases 1 \& 2}
\flowendcircle4\flowendrightpart
\flowendmiddlepart
\flowleftpart\flowcompute{cleanup}
\flowendcircle3\flowendleftpart
\flowendleftpart
\flowrightpart\flowcompute{restore}
\flowendcircle2\flowendrightpart}}