\documentclass{article}
\newcommand{\zyva}[2]
  {\left#1\begin{array}{cc}\hline\hline1&2\\3&4\end{array}\right#2}
\begin{document}
Fraction is centered:
$$
\zyva{[}{]} \times \zyva{\lceil}{\rfloor} \over \zyva{(}{)}
$$
You can see arrows:
$$\newcommand{\demo}[1]{\quad\quad#1{1 \times 2 \times \cdots \times n}\quad\texttt{\string#1}}%
\begin{array}{cc}
\demo{\overleftarrow} & \demo{\overrightarrow}
\end{array}
$$
The arrow extends properly
$$\overrightarrow{1234567890}$$
The arrows extend properly
$$
\alpha\quad\overrightarrow{1234567890}\quad\beta\quad\overleftarrow{9876543210}\quad\gamma
$$

\end{document}
