\documentclass{article}
\nonstopmode 
\usepackage{adigraph}
\begin{document}
\NewAdigraph{myAdigraph}{
s:0,0;
 1:2,2;
3:2,-2;
2:6,2;
 4:6,-2;
t:8,0;
}{
s,1:25;
s,3:25;
3,4:25;
1,2:35;
 2,t:20;
4,t:30;
3,1:10;
 4,2:10;
 2,3:15::near start;
 4,1:5::near start;
 }
\myAdigraph{
 s,3,4,2,t;
 }
\end{document}