\newcommand{\Equ}[1]{(\ref{#1})}
\def\Reals{\mathbb{R}}
-\definecolor{shadecolor}{rgb}{0.95,0.95,0.95}
%\newenvironment{Algo}{\vspace{-1em}\begin{center}\begin{minipage}[h]{0.95\columnwidth}\begin{shaded}\begin{tabbing}%
% \hspace{3mm}\=\hspace{3mm}\=\hspace{3mm}\=\hspace{3mm}\=\hspace{3mm}\=\hspace{3mm}\=\hspace{3mm}\= \kill} %
% { \end{tabbing}\vspace{-1em}\end{shaded}\end{minipage}\end{center}\vspace{-1em}}
label=#1, caption={#2}}
}{}
-\def\N{$\mathbb N$ }
+%\def\N{$\mathbb N$ }
\def\R{$\mathbb R$ }
\def\Z{$\mathbb Z$ }
\def\Q{$\mathbb Q$ }