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\usepackage{algorithm}
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\begin{document}
{
\floatname{algorithm}{Code}
\begin{algorithm}[h]
\caption{Rule evaluator for classical attribute grammar}\label{alg:ag-eval}
\begin{algorithmic}
\Procedure{\texttt{AG\_EVAL}}{$r, Val$}
\If{$r \equiv v_0 \texttt{=} g( v_1, \dots, v_n)$}
\State $Val(v_0) \gets g( Val(v_1), \dots, Val(v_n))$