A square with a dotted line in it with arrows reversed or in the same direction

Question

I want to draw the one of the squares of following figure:

And I want to know how to reverse this bold arrow please.

Thanks in advance!

Answer 1

Not the most elegant approach to the midway arrows but you can do this with plain tikz. (Better approaches to the arrows are described at TikZ: How to draw an arrow in the middle of the line? for a more involved figure.)

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw [thick] (3,0) -- (0,0) -- (0,3);
\draw [thick,  latex reversed-] (0,3)--(0,5)--(3,5);
\draw [thick, latex reversed-latex reversed] (3,5) -- (6,5) -- (6,3);
\draw [thick, -latex reversed] (6,3) -- (6,0) -- (3,0);
\draw [dashed] (0,2.5) -- (6,2.5) node [above, pos=.5] {c};
\node [draw=none, anchor=east] at (0,2.5) {3};
\node [draw=none, anchor=west] at (6,2.5) {4};
\node [draw=none, anchor=east] at (0,3) {a};
\node [draw=none, anchor=west] at (6,3) {a};
\node [draw=none, anchor=east] at (0,0) {5};
\node [draw=none, anchor=east] at (0,5) {1};
\node [draw=none, anchor=west] at (6,0) {6};
\node [draw=none, anchor=west] at (6,5) {2};
\node [draw=none, anchor=south] at (3,5) {b};
\node [draw=none, anchor=north] at (3,0) {b};
\end{tikzpicture}
\begin{tikzpicture}
\draw [thick] (3,0) -- (0,0) -- (0,3);
\draw [thick,  latex reversed-] (0,3)--(0,5)--(3,5);
\draw [thick, latex reversed-] (3,5) -- (6,5) -- (6,3);
\draw [thick, latex reversed-latex reversed] (6,3) -- (6,0) -- (3,0);
\draw [dashed] (0,2.5) -- (6,2.5) node [above, pos=.5] {c};
\node [draw=none, anchor=east] at (0,2.5) {$3'$};
\node [draw=none, anchor=west] at (6,2.5) {$4'$};
\node [draw=none, anchor=east] at (0,3) {a};
\node [draw=none, anchor=west] at (6,3) {a};
\node [draw=none, anchor=east] at (0,0) {$5'$};
\node [draw=none, anchor=east] at (0,5) {$1'$};
\node [draw=none, anchor=west] at (6,0) {$6'$};
\node [draw=none, anchor=west] at (6,5) {$2'$};
\node [draw=none, anchor=south] at (3,5) {b};
\node [draw=none, anchor=north] at (3,0) {b};
\end{tikzpicture}
\end{document}