Skip to main content\( \newcommand{\N}{\mathbb N} \newcommand{\Z}{\mathbb Z} \newcommand{\Q}{\mathbb Q} \newcommand{\R}{\mathbb R}
\newcommand{\MyTikzmark}[2]{
\tikz[overlay,remember picture,baseline] \node [anchor=base] (#1) {$#2$};}
\newcommand{\DrawVLine}[3][]{
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\draw[shorten \lt =0.3ex, #1] (#2.north) -- (#3.south);
\end{tikzpicture}
}
\newcommand{\DrawHLine}[3][]{
\begin{tikzpicture}[overlay,remember picture]
\draw[shorten \lt =0.2em, #1] (#2.west) -- (#3.east);
\end{tikzpicture}
}
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\)
