LatexConverter - escape { and }
The braces are not print by LaTeX unless escaped with \{
\begin{tabular}{|rl||c|c|}
\hline
\multicolumn{2}{|c||}{DFA} & a & b\\\hline
& {} & {} & {} \\\hline
$\rightarrow$ & {A} & {A, B} & {B} \\\hline
& {A, B} & {A, B, C} & {B} \\\hline
& {A, B, C} & {A, B, C} & {B, D} \\\hline
& {B} & {C} & {} \\\hline
$\leftarrow$ & {B, D} & {C, D} & {D} \\\hline
& {C} & {} & {D} \\\hline
$\leftarrow$ & {C, D} & {D} & {D} \\\hline
$\leftarrow$ & {D} & {D} & {D} \\\hline
\end{tabular}