# Reverse arrow in TikZ

How can I reverse some arrows of the diagram given by the code below?

\begin{tikzpicture}
% Tell it where the nodes are
\node (A) {$A$};
\node (B) [below=of A] {$B$};
\node (C) [right=of A] {$C$};
\node (D) [right=of B] {$D$};
% Tell it what arrows to draw
\draw[-stealth] (A)-- node[left] {\small $i$} (B);
\draw[-stealth] (B)-- node [below] {\small $g$} (D);
\draw[-stealth] (A)-- node [above] {\small $j$} (C);
\draw[-stealth] (C)-- node [right] {\small $k$} (D);
\end{tikzpicture}

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Do you want to add extra arrows or just change the direction of some of the existing arrows? –  Gonzalo Medina Dec 8 '11 at 20:23
Just to change the directions of some/all of them. Thank you –  Nadori Dec 8 '11 at 20:27

You can either interchange - and the specification of the arrow tip, or you can also interchange the order of the nodes; the following code shows both options:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{positioning}

\begin{document}

\begin{tikzpicture}
\node (A) {$A$};
\node (B) [below=of A] {$B$};
\node (C) [right=of A] {$C$};
\node (D) [right=of B] {$D$};
\draw[-stealth] (A)-- node[left] {\small $i$} (B);
\draw[-stealth] (B)-- node [below] {\small $g$} (D);
\draw[-stealth] (A)-- node [above] {\small $j$} (C);
\draw[-stealth] (C)-- node [right] {\small $k$} (D);
\end{tikzpicture}

\begin{tikzpicture}
\node (A) {$A$};
\node (B) [below=of A] {$B$};
\node (C) [right=of A] {$C$};
\node (D) [right=of B] {$D$};
\draw[stealth-] (A)-- node[left] {\small $i$} (B);
\draw[stealth-] (B)-- node [below] {\small $g$} (D);
\draw[-stealth] (C)-- node [above] {\small $j$} (A);
\draw[-stealth] (D)-- node [right] {\small $k$} (C);
\end{tikzpicture}

\end{document}


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