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\begin{document}
\begin{table}
\centering
\begin{adjustbox}{max width=\textwidth}
    \begin{tabular}{l||c|ccc}\toprule
Dataset         & Sparse PC  (ours)          & Bipartite flow~tran2019discrete    & AF/SCF~ziegler2019latent    & IAF/SCF~ziegler2019latent \\\midrule
Penn Tree Bank  & \textbf{1.35} & 1.38              &1.46       &1.63\\\bottomrule
    \end{tabular}
\end{adjustbox}
\caption{Table 2 : \label{tab:ptbchar}Character-level language modeling results on Penn Tree Bank in test set bpd.}
\end{table}
\end{document}