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\begin{document}
\begin{table}
\centering
\begin{adjustbox}{max width=\textwidth}
        \begin{tabular}{l|c|c}
             & Objectworld (sec)  & Highway (sec)\\
            \hline
             ELIRL & \ \ $17.055\pm0.091$ & $21.438\pm0.173$\\
             ELIRLre & \ \ $17.068\pm0.091$ & $21.440\pm0.173$\\
             MaxEnt IRL & \ \ $16.572\pm0.407$ & $18.283\pm0.775$ \\
             GPIRL &  $1008.181\pm67.261$ & $392.117\pm18.484$\\
        \end{tabular}
\end{adjustbox}
\caption{Table 1 : The average learning time per task. The standard error is reported after the $\pm$.}
\end{table}
\end{document}