\documentclass[a4paper,11pt]{article}

\usepackage{ngerman}
\usepackage{amsmath,amsfonts,amssymb,amsthm}

\usepackage{tikz}
\usetikzlibrary{arrows,chains,matrix,positioning,scopes}
\usetikzlibrary{arrows.meta}
\usetikzlibrary{math}

\def\O{\mathcal{O}}
\def\sort{\mathrm{sort}}
\def\scan{\mathrm{scan}}
\def\dist{\mathrm{dist}}
\def\Z{\mathbb{Z}}
\def\Q{\mathbb{Q}}
\def\R{\mathbb{R}}
\def\E{\mathbb{E}}


\begin{document}


\textbf{Aufgabe 2}
\begin{center}
	\begin{tikzpicture}[scale=0.8,every node/.style={circle,inner sep=1mm,minimum size=2mm}]
	\node[draw,circle] at (0, 2.4) (a) {};
	\node[draw,circle] at (1, 3.4) (b) {};
	\node[draw,circle] at (2.4, 3.4) (c) {};
	\node[draw,circle] at (3.4, 2.4) (d) {};
	\node[draw,circle] at (3.4, 1) (e) {};
	\node[draw,circle] at (2.4, 0) (f) {};
	\node[draw,circle] at (1, 0) (g) {};
	\node[draw,circle] at (0, 1) (h) {};
	
	\path[-,>=triangle 60,shorten >=0pt,every node/.style={font=\small}]
	(a) edge node () {} (b)
	(c) edge node () {} (d)
	(e) edge node () {} (f)
	(g) edge node () {} (h)
	(b) edge node () {} (g)
	(c) edge node () {} (f)
	(a) edge node () {} (d)
	(h) edge node () {} (e)
	;
	\end{tikzpicture}
\end{center}


\end{document}