%*****************************
% dcfs07.cls -- document class file
% Created by Viliam Geffert, Dec 14, 2006
%      Files coming with this distribution:
%      dcfs07.cls -- document class itself [this file]
%      dcfs07ex.tex -- a sample input with embedded %-comments
%      dcfs07qk.pdf, dcfs07qk.ps -- quick reference handbook,
%        containing a brief summary of all commands
%      dcfs07dc.pdf, dcfs07dc.ps -- guidebook for authors,
%        containing a more detailed documentation about the class
%      ****************
%      Available for volume editors only:
%      acc.clo -- activating [acc*] mode for dcfs07.cls
%      dcfs07qk.tex -- latex source for quick reference handbook
%      dcfs07dc.tex -- latex source for guidebook for authors
%
\NeedsTeXFormat{LaTeX2e}%
\ProvidesClass{dcfs09}[2006/12/14 dcfs09]%
%
%!!Options supported by dcfs07 class:
%  "sub" --final version for submission, hiding authors' identity
%  "acc" --final version for proceedings
\DeclareOption{sub}{\newcommand*{\d@rbannr}{}}%!![sub] := YES/NO
\DeclareOption{acc}{\AtEndOfClass{\IfFileExists{acc.clo}%
  {\input{acc.clo}}{\renewcommand*{\PCappendix}{\end{document}}}}}
   %!![acc] := YES/NO
%
%!!The following `article' class options should not be used,
%  so they will be ignored, for compatibility reasons:
\DeclareOption{10pt}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `10pt' ignored (default 11pt)}}}
\DeclareOption{11pt}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `11pt' ignored (default)}}}
\DeclareOption{12pt}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `12pt' ignored (default 11pt)}}}
\DeclareOption{openlib}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `openlib' ignored}}}
\DeclareOption{leqno}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `leqno' ignored}}}
\DeclareOption{fleqn}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `fleqn' ignored}}}
\DeclareOption{titlepage}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `titlepage' ignored}}}
\DeclareOption{twocolumn}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `twocolumn' ignored}}}
\DeclareOption{a4paper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `a4paper' ignored}}}
\DeclareOption{letterpaper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `letterpaper' ignored}}}
\DeclareOption{a5paper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `a5paper' ignored}}}
\DeclareOption{b5paper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `b5paper' ignored}}}
\DeclareOption{executivepaper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `executivepaper' ignored}}}
\DeclareOption{legalpaper}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `legalpaper' ignored}}}
\DeclareOption{twoside}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `twoside' ignored (default)}}}
\DeclareOption{oneside}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `oneside' ignored (default twoside)}}}
\DeclareOption{landscape}{\AtEndOfClass{\ClassWarning{dcfs07}%
  {Option `landscape' ignored}}}
%
%!!Remaining options passed to `article' class:
\DeclareOption*{\PassOptionToClass{\CurrentOption}{article}}
\ProcessOptions\relax
\LoadClass[twoside,11pt]{article}%
%
%!!Processing [sub] option, part I
\@ifundefined{d@rbannr}{%!!if [sub] = NO, standard:
  \newcommand{\d@phantom}[1]{\mbox{{#1}}}%
  \newcommand{\d@markboth}[2]{\markboth{#1}{#2}}%
 }{%!!if [sub] = YES, hide authors' identity:
  \newcommand{\d@phantom}[1]{\mbox{\phantom{#1}}}%
  \newcommand{\d@markboth}[2]{\markboth{#2}{#2}}%
}
%!!Commands reserved for volume editors (handling [acc*] mode)
\newcommand*{\dpagerange}{\mbox{!!!! $\backslash$dpagerange !!!!}}
\newcounter{dlastpage}\let\thedlastpage\relax

%*****************************
%!!Style formatting parameters
%
\setlength{\textheight}{21.25cm}
\setlength{\textwidth}{13.5cm}
\setlength{\topmargin}{0.4cm}
\setlength{\oddsidemargin}{1.3cm}
\setlength{\evensidemargin}{1.3cm}
\flushbottom
\setlength{\parskip}{0pt\@plus1.3pt}

\setlength{\footnotesep}{9.0pt}
\setlength{\arraycolsep}{2.3pt}
\setlength{\tabcolsep}{2.3pt}
\setlength{\doublerulesep}{1.7pt}

\setlength{\intextsep}{10pt\@plus2pt\@minus2pt}
\setlength{\textfloatsep}{11pt\@plus2pt\@minus2pt}
\setlength{\floatsep}{9pt\@plus2pt\@minus2pt}
\renewcommand{\textfraction}{.3}
\renewcommand{\floatpagefraction}{.5}

%!!modified clone
\renewcommand\normalsize{%
   \@setfontsize\normalsize\@xipt{13.6}%
   \abovedisplayskip 9\p@\@plus2\p@\@minus4\p@
   \abovedisplayshortskip \z@\@plus2\p@\@minus1\p@
   \belowdisplayshortskip 6.5\p@\@plus2\p@\@minus3\p@
   \belowdisplayskip \abovedisplayskip
   \let\@listi\@listI}
\normalsize

%!!modified clone
\renewcommand\small{%
   \@setfontsize\small\@xpt\@xiipt
   \abovedisplayskip 8\p@\@plus1.8\p@\@minus3\p@
   \abovedisplayshortskip \z@\@plus1.8\p@\@minus0.8\p@
   \belowdisplayshortskip 6\p@\@plus2\p@\@minus3\p@
   \def\@listi{\@listI}%
   \belowdisplayskip \abovedisplayskip
}

%*****************************
%!!Reductions from the standard article (see also \maketitle)
%
\renewcommand*{\tableofcontents}{}
\renewcommand*{\listoffigures}{}
\renewcommand*{\listoftables}{}
\renewcommand*{\makeindex}{}
\renewcommand*{\makeglossary}{}
\pagenumbering{arabic}%
\renewcommand*{\pagenumbering}[1]{\ignorespaces}
\renewcommand*{\reversemarginpar}{}
\renewcommand*{\normalmarginpar}{}
\renewcommand*{\twocolumn}{\d@err}
\renewcommand*{\part}{\d@err}
\renewcommand*{\date}[1]{\ignorespaces}\let\@date\relax
\renewcommand*{\and}{\d@err}
\renewcommand*{\marginpar}{\d@err}

%*****************************
%!!Modified clones for sectioning and bibliography
%
\renewcommand{\section}{\@startsection{section}{1}{\z@}{-3.25ex%
  \@plus-1.3ex\@minus-0.2ex}{1.5ex\@plus.25ex}{\normalfont\Large\bfseries}}
\renewcommand{\subsection}{\@startsection{subsection}{2}{\z@}%
  {-3.0ex\@plus-1.2ex\@minus-0.2ex}{1.5ex%
  \@plus.25ex}{\normalfont\large\bfseries}}
\renewcommand{\subsubsection}{\@startsection{subsubsection}{3}%
  {\z@}{-3.0ex\@plus-1.2ex\@minus-0.2ex}{1.5ex%
  \@plus.25ex}{\normalfont\normalsize\bfseries}}
\renewcommand{\paragraph}{\@startsection{paragraph}{4}{\z@}%
  {2.25ex\@plus1.1ex\@minus0.2ex}{-0.5em}{\normalfont\normalsize\bfseries}}
\renewcommand{\subparagraph}{\@startsection{subparagraph}{4}%
  {\parindent}{2.25ex\@plus1.1ex%
  \@minus0.2ex}{-0.5em}{\normalfont\normalsize\bfseries}}

\renewcommand*{\newblock}{\hskip .11em\@plus.11em\@minus.07em}
\renewcommand{\thebibliography}[1]{\section*{\refname}\small
  \list{\@biblabel{\arabic{enumiv}}}{%
    \settowidth{\labelwidth}{\@biblabel{#1}}%
    \setlength{\leftmargin}{\labelwidth}%
      \addtolength{\leftmargin}{\labelsep}%
    \setlength{\parsep}{0ex\@plus0.2ex\@minus0.04ex}%
    \setlength{\itemsep}{0.9ex}%
    \usecounter{enumiv}\let\p@enumiv\@empty%
    \renewcommand\theenumiv{\arabic{enumiv}}%
  }%
  \sloppy \clubpenalty4000%
  \@clubpenalty\clubpenalty \widowpenalty4000%
  \sfcode`\.\@m}%
\renewcommand{\endthebibliography}{\renewcommand{\@noitemerr}{\@warning{Empty
  `thebibliography' environment}}%
\endlist}

%*****************************
%!!Modified clones for lists and captions
%
\renewcommand{\@makecaption}[2]{%
  \@tempdima\hsize \advance\@tempdima-34pt%!!=2\parindent
  \setbox\@tempboxa\hbox{{\normalfont\footnotesize{\bfseries #1.}\ #2}}%
  \ifdim\wd\@tempboxa<\@tempdima%
    \hfil{\normalfont\footnotesize{\bfseries #1.}\ #2}\hfil
   \else
    \setbox\@tempboxa\hbox{{\normalfont\footnotesize{\bfseries #1.}\ }}%
    \advance\@tempdima-\wd\@tempboxa%
    \hbox to\hsize{\hfil{\normalfont\footnotesize\bfseries
      #1.}\ \parbox[t]\@tempdima{\normalfont\footnotesize #2}\hfil}%
  \fi
}

\renewcommand*{\labelenumi}{(\theenumi)}
\renewcommand*{\theenumi}{$\scriptstyle\mathrm{\Roman{enumi}}$}

\renewcommand*{\labelenumii}{(\theenumii)}
\renewcommand*{\theenumii}{$\scriptstyle\mathrm{\Alph{enumii}}$}
\renewcommand*{\p@enumii}{\theenumi.}

\renewcommand*{\labelenumiii}{(\theenumiii)}
\renewcommand*{\theenumiii}{$\scriptstyle\mathrm{\arabic{enumiii}}$}
\renewcommand*{\p@enumiii}{\p@enumii\theenumii.}

\renewcommand*{\labelenumiv}{(\theenumiv)}
\renewcommand*{\theenumiv}{$\scriptstyle\mathrm{\alph{enumiv}}$}
\renewcommand*{\p@enumiv}{\p@enumiii\theenumiii.}

\renewcommand*{\labelitemi}{$\bullet$}
\renewcommand*{\labelitemii}{$\ast$}
\renewcommand*{\labelitemiii}{$\circ$}
\renewcommand*{\labelitemiv}{$\scriptstyle\diamond$}

\renewcommand{\descriptionlabel}[1]{\setbox\@tempboxa\hbox{#1}%
  \ifdim\wd\@tempboxa<\labelwidth \makebox[\labelwidth][l]{#1}%
    \else {#1}\fi
}
\renewcommand*{\makelabel}{}
\renewcommand{\description}{%
\list{}{\let\makelabel\descriptionlabel}}%
\renewcommand{\enddescription}{\endlist}

\setlength{\leftmargini}{2\parindent}
\setlength{\leftmarginii}{\parindent}
\setlength{\leftmarginiii}{\parindent}
\setlength{\leftmarginiv}{\parindent}
\setlength{\leftmarginv}{\parindent}
\setlength{\leftmarginvi}{\parindent}

\setlength{\leftmargin}{\leftmargini}
\setlength{\labelsep}{.5em}
\setlength{\labelwidth}{\leftmargini}
  \addtolength{\labelwidth}{-\labelsep}

\renewcommand{\@listI}{\setlength{\leftmargin}{\leftmargini}%
  \setlength{\rightmargin}{0pt}%
  \setlength{\labelsep}{0.75em}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}%
  \setlength{\listparindent}{\parindent}%
  \setlength{\itemindent}{0em}%
  \setlength{\partopsep}{0.6\baselineskip\@plus0.3ex\@minus0.1ex}%
  \setlength{\topsep}{0.4ex}%
  \setlength{\itemsep}{0.4ex}%
  \setlength{\parsep}{0ex\@plus1.3pt}%
}

\let\@listi\@listI
\@listi

\renewcommand{\@listii}{\setlength{\leftmargin}{\leftmarginii}%
  \setlength{\rightmargin}{0pt}%
  \setlength{\labelsep}{0.75em}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}%
  \setlength{\listparindent}{\parindent}%
  \setlength{\itemindent}{0em}%
  \setlength{\partopsep}{0.5\baselineskip\@plus0.2ex\@minus0.1ex}%
  \setlength{\topsep}{0.3ex}%
  \setlength{\itemsep}{0.3ex}%
  \setlength{\parsep}{0ex\@plus1.3pt}%
}

\renewcommand{\@listiii}{\setlength{\leftmargin}{\leftmarginiii}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}}

\renewcommand{\@listiv}{\setlength{\leftmargin}{\leftmarginiv}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}}

\renewcommand{\@listv}{\setlength{\leftmargin}{\leftmarginv}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}}

\renewcommand{\@listvi}{\setlength{\leftmargin}{\leftmarginvi}%
  \setlength{\labelwidth}{\leftmargin}%
    \addtolength{\labelwidth}{-\labelsep}}

%*****************************
%!!Built-in theorem-like environments
%
\newtheorem{theorem}{Theorem}
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{corollary}[theorem]{Corollary}
\newtheorem{proposition}[theorem]{Proposition}
\newtheorem{problem}[theorem]{Problem}
\newtheorem{definition}[theorem]{Definition\dromanb}
\newtheorem{remark}[theorem]{Remark\dromanb}
\newtheorem{example}[theorem]{Example\dromanb}
\newtheorem{claim}{\itshape Claim\d@cproof}
\newcommand*{\dromanb}{\gdef\d@tstyle{\rmfamily\upshape\mdseries}}

\newcommand{\d@tstyle}{}
\renewcommand{\@begintheorem}[2]{%
  \par\gdef\d@tstyle{\rmfamily\itshape\mdseries}\trivlist
  \item[\hskip\labelsep{\rmfamily\upshape\bfseries
    #1\ #2.}]\d@tstyle\ignorespaces}
\renewcommand{\@opargbegintheorem}[3]{%
  \par\gdef\d@tstyle{\rmfamily\itshape\mdseries}\trivlist
  \item[\hskip\labelsep{\rmfamily\upshape\bfseries
    #1\ #2\hskip\labelsep #3.}]\d@tstyle\ignorespaces}
\newcounter{d@proof}\let\thed@proof\relax\setcounter{d@proof}{0}
\newcommand*{\d@cproof}{%
  \ifnum \value{d@proof}=0{\@warning{\protect\begin{claim} ...
    \protect\end{claim} not nested in any `proof'^^J or `proofof'
    environment,}}\else\fi
}

\newcommand*{\qed}{\raisebox{0.5ex}[0ex][0ex]{\framebox[1ex][l]{}}}

\newenvironment{proof}{%
  \ifnum \value{d@proof}=0{\setcounter{claim}{0}}\else\fi
  \stepcounter{d@proof}\par\noindent
  {\rmfamily\itshape\mdseries Proof\/}:\hspace{\labelsep}\ignorespaces}%
  {\addtocounter{d@proof}{-1}\mbox{}\nolinebreak\hfill~%
  \ifnum \value{d@proof}=0{\qed}\else
    \ifnum \value{d@proof}=1{\qed\nolinebreak\,\nolinebreak\qed}\else
      \ifnum \value{d@proof}=2{\qed\nolinebreak\,\nolinebreak\qed
          \nolinebreak\,\nolinebreak\qed}\else
        {\qed\nolinebreak...\nolinebreak\qed}%
  \fi\fi\fi
  \medbreak
}
\newenvironment{proofof}[1]{%
  \vspace{\parskip}\vspace{\topsep}\vspace{\partopsep}%
  \ifnum \value{d@proof}=0{\setcounter{claim}{0}}\else\fi
  \stepcounter{d@proof}\par\noindent
  {\rmfamily\upshape\bfseries Proof of #1.}\hspace{\labelsep}\ignorespaces}%
  {\addtocounter{d@proof}{-1}\mbox{}\nolinebreak\hfill~%
  \ifnum \value{d@proof}=0{\qed}\else
    \ifnum \value{d@proof}=1{\qed\nolinebreak\,\nolinebreak\qed}\else
      \ifnum \value{d@proof}=2{\qed\nolinebreak\,\nolinebreak\qed
          \nolinebreak\,\nolinebreak\qed}\else
        {\qed\nolinebreak...\nolinebreak\qed}%
  \fi\fi\fi
  \medbreak
}
%*****************************
%!!
\renewcommand{\title}{}% {text \\of \\title}
\newcommand{\d@title}{}
\newcommand{\d@drtitle}{}
% VAR \d@title --command (global string to expand)
% VAR \d@drtitle --command (global string to expand)
%
\def\title#1{%
  \gdef\d@title{#1}\gdef\d@drtitle{#1}%
  \let\author\d@oldauthor
  \let\address\d@oldaddress
  \let\thanks\d@oldthanks
  \let\thanksmark\d@oldthanksmark
  \let\runningtitle\d@oldrunningtitle
  \let\runningauthors\d@oldrunningauthors
  \let\maketitle\d@oldmaketitle
  \def\title{\d@ahtwice}%
}
%!!clone of "\title"

%*****************************
%!!
\renewcommand{\author}{}% [list of p_labels]{name of 1 author}
\newcommand{\d@bauthor}{}\newcommand{\d@and}{}
\newcommand{\d@drauthor}{}\newcommand{\d@drand}{}
% VAR \d@bauthor{} --command (string to expand)
% VAR \d@and{}     --command (string separating authors)
% VAR \d@drauthor  --command (string to expand)
% VAR \d@drand{}    --command (string separating running authors)
%
\def\author{\@ifnextchar[{\d@dauthor}{\d@sauthor}}
%!!clone of "\author"
\def\d@bauthor{}\def\d@and{}
\def\d@drauthor{}\def\d@drand{}

\newcommand{\d@dauthor}{}%--list of p_labels present
\def\d@dauthor[#1]#2{\d@thanksmark{#1}%
  \xdef\d@bauthor{\d@bauthor\d@and\mbox{#2{}{\d@bthanksmark}}}%
  \def\d@and{\hskip 1em\@plus.17fil{}}%
  \xdef\d@drauthor{\d@drauthor\d@drand{#2}}%
  \def\d@drand{{}, }%
}

\newcommand*{\d@sauthor}[1]{%--list of p_labels missing
  \xdef\d@bauthor{\d@bauthor\d@and\mbox{#1}}%
  \def\d@and{\hskip 1em\@plus.17fil{}}%
  \xdef\d@drauthor{\d@drauthor\d@drand{#1}}%
  \def\d@drand{{}, }%
}

%*****************************
%!!
\newcommand{\address}{}% [p_label]{text //of //address}
% VAR \d@baddress,\d@temp --boxes
%
\def\address{\@ifnextchar[{\d@daddress}{\d@saddress}}
\newsavebox{\d@baddress}\newsavebox{\d@temp}
\savebox{\d@baddress}[\linewidth][t]{\centering\normalsize}

\newcommand{\d@daddress}{}%--p_label present
\def\d@daddress[#1]#2{\d@label{#1}%
  \savebox{\d@temp}[\linewidth][t]{%
    \begin{minipage}[t]{\linewidth}\centering\normalsize
      \usebox{\d@baddress}\\
      ${}^{(\d@ref{#1})}$\rule[0pt]{0pt}{3.5ex}{#2}%
    \end{minipage}%
  }%
  \savebox{\d@baddress}[\linewidth][t]{\usebox{\d@temp}}%
}

\newcommand*{\d@saddress}[1]{%--p_label missing
  \savebox{\d@temp}[\linewidth][t]{%
    \begin{minipage}[t]{\linewidth}\centering\normalsize
      \usebox{\d@baddress}\\ \rule[0pt]{0pt}{3.5ex}{#1}%
    \end{minipage}%
  }%
  \savebox{\d@baddress}[\linewidth][t]{\usebox{\d@temp}}%
}

%*****************************
%!!Auxiliary support for \address
%
\newcommand*{\withinline}{\unskip\ -- \ignorespaces}

\newcommand{\email}{}% [short author's name]{email address text}
\def\email{\@ifnextchar[{\d@demail}{\d@semail}}

\newcommand{\d@demail}{}%--short author's name present
\def\d@demail[#1]#2{\mbox{%
  \hspace*{0.5em}{\small\textsf{#2} {(#1)}}\hspace*{0.5em}%
}}

\newcommand*{\d@semail}[1]{%--short author's name missing
\mbox{\hspace*{0.5em}{\small\textsf{#1}}\hspace*{0.5em}}}

%*****************************
%!!
\renewcommand{\thanks}{}% [p_label]{text //to //footnote}
\def\thanks{\@ifnextchar[{\d@dthanks}{\d@sthanks}}
\renewcommand{\@thanks}{}\let\@thanks\relax %!!not used, cleared

\newcommand{\d@dthanks}{}%--p_label present
\long\def\d@dthanks[#1]#2{\d@label{#1}%
  \d@oldfootnotetext[0]{\hspace*{-1.8em}%
    \d@phantom{%!!
      \begin{minipage}[t]{\linewidth}\footnotesize
        \makebox[1.8em][r]{${}^{(\d@ref{#1})}$}\rule[1.7ex]{0em}{1ex}{#2}%
      \end{minipage}%
    }%!!end\d@phantom
  }%
}
%!!--space "1.8em" taken from "\def\@makefntext"

\newcommand{\d@sthanks}[1]{%--p_label missing
  \d@oldfootnotetext[0]{\hspace*{-1.8em}%
    \d@phantom{%!!
      \begin{minipage}[t]{\linewidth}\footnotesize
        \makebox[1.8em][r]{}\rule[1.7ex]{0em}{1ex}{#1}%
      \end{minipage}%
    }%!!end\d@phantom
  }%
}
%!!--space "1.8em" taken from "\def\@makefntext"

%*****************************
%!!
\newcommand{\thanksmark}{}% {list of p_labels}
\newcommand{\d@bthanksmark}{}\newcommand{\d@thanksmsep}{}
\newcommand{\d@thankslab}{}
% VAR \d@bthanksmark --command (global string to expand)
% VAR \d@thanksmsep  --command (string separating p_labels)
% VAR \d@thankslab   --command (loop control variable)
%
\def\thanksmark#1{\d@thanksmark{#1}\mbox{\d@bthanksmark}}

\newcommand*{\d@thanksmark}[1]{% {list of p_labels} => \d@bthanksmark
  \def\d@thanksmsep{}\def\d@bthanksmark{}%
  \@for\d@thankslab:=#1\do{%
    \xdef\d@bthanksmark{\d@bthanksmark\d@thanksmsep
      \d@ref{\d@thankslab}%
    }%
    \def\d@thanksmsep{,}%
  }%
  \xdef\d@bthanksmark{${}^{\scriptscriptstyle(\d@bthanksmark)}$}%
}

%*****************************
%!!
\newcommand{\runningtitle}{}% {text of running title}
\newcommand{\d@ertitle}{}\let\d@ertitle\relax
% VAR \d@ertitle --command (global string to expand)
%
\def\runningtitle#1{%
  \gdef\d@ertitle{#1}\def\runningtitle{\d@ahtwice}%
}

\newcommand{\runningauthors}{}% {text of running authors}
\newcommand{\d@erauthor}{}\let\d@erauthor\relax
% VAR \d@erauthor --command (global string to expand)
%
\def\runningauthors#1{%
  \gdef\d@erauthor{#1}\def\runningauthors{\d@ahtwice}%
}

%*****************************
%!!Auxiliary internal commands for preamble labels
%!!Counterparts of "\newlabel", "\label" and "\ref", via .aux file
%
\newcommand*{\dnewlabel}[1]{% {p_label}
\@ifundefined{c@#1}{%
  \stepcounter{footnote}\newcounter{#1}%
  \setcounter{#1}{\value{footnote}}%
}{}}
%!!--executed in .aux file, before preamble
%!!--counterpart of "\newlabel"

\newcommand*{\d@ref}[1]{% {p_label}
  \@ifundefined{c@#1}{{X}\write\@unused{DCFS Class Warning:
    Preamble label `#1' undefined}}%
   {\ifnum \value{#1}=0{}\else {\Alph{#1}}\fi
  }%
}
%!!--detour by "\write", because of bug in "\@warning"
%!!--counterpart of "\ref"

\newcommand*{\d@label}[1]{% {p_label}
  \@ifundefined{c@#1}{\@warning{Preamble labels have changed^^J --
      rerun to get references right}%
    \newcounter{#1}\setcounter{#1}{24}%!!displayed as "X"
  }{}%
  \@bsphack
    \protected@write\@auxout{}{\string\dnewlabel{#1}}%
  \@esphack
}
%!!--clone of "\label"

%*****************************
%!!Auxiliary internal commands for warning messages
%
\newcommand*{\d@ahtitle}{%--warning: "ahead of \title"
  \@warning{Illegal command in preamble,}%
  \typeout{\space\space\space
    -- DCFS document class prohibits some commands, until}%
  \typeout{\space\space\space\space\space\space\space\space
    \protect\title\space has been completed.}%
  \typeout{\space\space\space
    -- For proper formatting of the title page, see DCFS
    documentation,}%
  \typeout{\space\space\space\space\space\space\space\space
    files `dcfs07dc.ps' or `dcfs07dc.pdf'.}%
}

\newcommand*{\d@ahmaketitle}{%--warning: "ahead of \maketitle"
  \@warning{Illegal command in preamble,}%
  \typeout{\space\space\space
    -- DCFS document class prohibits some standard features}%
  \typeout{\space\space\space\space\space\space\space\space
    (like, e.g., abstract or standard \protect\footnote...
    handling), until}%
  \typeout{\space\space\space\space\space\space\space\space
    \protect\maketitle\space has been completed.}%
  \typeout{\space\space\space
    -- For proper formatting of the title page, see DCFS
    documentation,}%
  \typeout{\space\space\space\space\space\space\space\space
    files `dcfs07dc.ps' or `dcfs07dc.pdf'.}%
}

\newcommand*{\d@ahtwice}{%--warning: "command used twice"
  \@warning{This DCFS command cannot be used for the second
    time,^^J ignored}%
}

\newcommand*{\d@ahover}{%--warning: "below \maketitle"
  \@warning{DCFS preamble command used below \protect\maketitle,}}

\newcommand*{\d@err}{%--error: "not allowed"
  \ClassError{dcfs07}{Some commands (\protect\and, \protect\marginpar,
    \protect\twocolumn\space ...)^^J are not allowed in dcfs style,
    please fix the problem by yourself}%
  {see DCFS documentation, files `dcfs07dc.ps' or `dcfs07dc.pdf'}%
}

%*****************************
%!!
\renewcommand{\maketitle}{%!!modified clone
  \par\begingroup
    \def\@makefnmark{\hbox to\z@{$\m@th^{\@thefnmark}$\hss}}%
    \global\@topnum\z@%!!Prevents figures from going at top of page
    \@maketitle
  \endgroup
  \pagestyle{myheadings}\thispagestyle{empty}%
%!!Work done, cleaning up:
  \let\ds@sub\relax
  \let\d@phantom\relax
  \let\d@markboth\relax
  \def\title{\d@ahover}%
    \let\d@title\relax
    \let\d@drtitle\relax
  \def\author{\d@ahover}%
    \let\d@bauthor\relax
    \let\d@and\relax
    \let\d@drauthor\relax
    \let\d@drand\relax
    \let\d@dauthor\relax
    \let\d@sauthor\relax
    \let\d@oldauthor\relax
  \def\address{\d@ahover}%
    \savebox{\d@baddress}[0.0em][t]{}%
    \savebox{\d@temp}[0.0em][t]{}%
    \let\d@baddress\relax
    \let\d@temp\relax
    \let\d@daddress\relax
    \let\d@saddress\relax
    \let\d@oldaddress\relax
  %\def\withinline{\d@ahover} %!!Not off, on purpose!
  %\def\email{\d@ahover} %!!Not off, on purpose!
    %\let\d@demail\relax %!!Not off, on purpose!
    %\let\d@semail\relax %!!Not off, on purpose!
  \def\thanks{\d@ahover}%
    \let\d@dthanks\relax
    \let\d@sthanks\relax
    \let\d@oldthanks\relax
  \def\thanksmark{\d@ahover}%
    \let\d@bthanksmark\relax
    \let\d@thanksmsep\relax
    \let\d@thankslab\relax
    \let\d@thanksmark\relax
    \let\d@oldthanksmark\relax
  \def\runningtitle{\d@ahover}%
    \let\d@ertitle\relax
    \let\d@oldrunningtitle\relax
  \def\runningauthors{\d@ahover}%
    \let\d@erauthor\relax
    \let\d@oldrunningauthors\relax
  \let\d@ref\relax
  \let\d@label\relax
  \let\d@ahtitle\relax
  \gdef\d@ahmaketitle{}%
  \let\d@ahtwice\relax
  \let\@maketitle\relax
    \let\d@rbannr\relax
    \let\d@lbannr\relax
    \let\d@oldll\relax
    \let\d@oldnewline\relax
    \let\d@oldlinebreak\relax
  \let\d@oldmaketitle\relax
  %\let\dpagerange\relax %!!Not off, on purpose!
    %\let\c@dlastpage\relax %!!Not off, on purpose!
  \let\footnote\d@oldfootnote
  \let\footnotemark\d@oldfootnotemark
  \let\footnotetext\d@oldfootnotetext
  \let\d@oldfootnote\relax
  \let\d@oldfootnotemark\relax
  \let\d@oldfootnotetext\relax
  \def\thefootnote{\arabic{footnote}}%
  \setcounter{footnote}{0}%
  \renewcommand*{\pagestyle}[1]{}% %!!\thispagestyle allowed
  \renewcommand{\markright}[1]{}%
  \renewcommand{\markboth}[2]{}%
  \typeout{\space\space\space\space...done}%
  \def\maketitle{\d@ahover}%
}
%!!clone of "\maketitle"

%!!Processing [sub] option, part II
\@ifundefined{d@rbannr}{%!!if [sub] = NO:
  \newcommand*{\d@rbannr}{%
    Descriptional Complexity of Formal Systems\\
    $\!\!\!$(Draft)\hfill
    Deadline for submissions: April 20, 2009\\
    Final versions: June 18, 2009%
  }%
 }{%!!if [sub] = YES:
  \renewcommand*{\d@rbannr}{%
    Descriptional Complexity of Formal Systems\\
    $\!\!\!$(Submission)\hfill
    Referees, please send your reports by May 25, 2009\\
    \mbox{}%
  }%
}

\newcommand*{\d@lbannr}{%
  \begin{minipage}[t]{0em}\flushleft\huge\itshape
    \makebox[0em][l]{$\mathcal{D}\!\mathcal{C}\!\!%
      \mathcal{F}\!\!\mathcal{S}$}\\[-1.2ex]%
    \makebox[0em][l]{\itshape\,\,\,\,2$\!$0$\!$0$\!$9}%
  \end{minipage}%
}

\renewcommand{\@maketitle}{%!!modified clone
  \typeout{DCFS: Building title page...}%
  \newpage\null\mbox{}\vspace{-2.30cm}%
  \begin{center}%
    \begin{minipage}[t]{0.09\linewidth}\flushleft\scriptsize
      \d@lbannr\hspace*{0.13em}%
      \raisebox{-0.33ex}[0ex][0ex]{\d@lbannr}%
    \end{minipage}\hfill
    \begin{minipage}[t]{0.88\linewidth}\flushright\scriptsize
      \mbox{}\\[-5.4ex]\d@rbannr
    \end{minipage}\\
    \mbox{}\vspace{1.0ex}\par
    \def\thanksmark##1{\@@warning{thanksmark in illegal
        location !!!}[!!!!
        $\backslash$thanksmark in illegal location !!!!]}%
      %!!set up running title and running author(s):
      %!!turn off "\\", "\newline", "\linebreak":
        \let\d@oldll\\ \def\\{\unskip\ \ignorespaces}%
        \let\d@oldnewline\newline
          \def\newline{\unskip\ \ignorespaces}%
        \let\d@oldlinebreak\linebreak
          \def\linebreak{\unskip\ \ignorespaces}%
        \typeout{DCFS: Preparing title and author(s) for running
          headlines...}%
        \@ifundefined{d@ertitle}{}{\gdef\d@drtitle{\d@ertitle}}%
        \@ifundefined{d@erauthor}{}{\gdef\d@drauthor{\d@erauthor}}%
        \d@markboth{\d@drauthor}{\d@drtitle}%
        %!!testing correctness of running author(s) and running title:
        \sbox{\d@temp}{\d@drauthor}\sbox{\d@temp}{\d@drtitle}%
      %!!turn on "\\", "\newline", "\linebreak":
      \let\\\d@oldll
        \let\newline\d@oldnewline \let\linebreak\d@oldlinebreak
      \typeout{DCFS: Preparing title for the first page...}%
      {\LARGE \d@title\\ \mbox{}}\par
      \typeout{DCFS: Preparing author(s) for the first page...}%
      \d@phantom{%!!
        \begin{minipage}[t]{0.9\linewidth}\centering\large
          \d@bauthor{}\mbox{}\\[-1.3ex]%
          \mbox{}%
        \end{minipage}%
      }%!!end\d@phantom
    \let\thanksmark\d@oldthanksmark
    \par
    \typeout{DCFS: Preparing addresses...}%
    \d@phantom{%!!
      \usebox{\d@baddress}%
    }%!!end\d@phantom
  \end{center}%
  \mbox{}\par
}
%!!clone of "\@maketitle"

%*****************************
%!!Small extensions to the standard article
%!!(except for preamble and theorem-like environments)
%
\renewenvironment{abstract}{%
  \@ifundefined{@maketitle}{}{\d@ahmaketitle}%
  \begin{quotation}\small\noindent
    {\bfseries Abstract.}\hspace{\labelsep}\ignorespaces}%
{\unskip\end{quotation}\ignorespaces}

\newcommand*{\keywords}{\unskip\mbox{}\\ \mbox{}\\
  {\bfseries Keywords:}\hspace{\labelsep}\ignorespaces}

\newcommand*{\PCappendix}{\clearpage
  \section*{Appendix for the Program Committee}\appendix
  \renewcommand*{\thepage}{A\,-\,\arabic{page}}%
}

%*****************************
%!!Global initial declarations
%
%!!just for using the fact that \roman{0}=blank :
\renewcommand*{\thefootnote}{\roman{footnote}}
\setcounter{footnote}{0}

\newcommand*{\d@oldll}{}
\newcommand*{\d@oldnewline}{}
\newcommand*{\d@oldlinebreak}{}
\newcommand*{\d@oldauthor}{}
\newcommand*{\d@oldaddress}{}
\newcommand*{\d@oldthanks}{}
\newcommand*{\d@oldthanksmark}{}
\newcommand*{\d@oldrunningtitle}{}
\newcommand*{\d@oldrunningauthors}{}
\newcommand*{\d@oldmaketitle}{}
\newcommand*{\d@oldfootnote}{}
\newcommand*{\d@oldfootnotemark}{}
\newcommand*{\d@oldfootnotetext}{}

\let\d@oldauthor\author
\let\d@oldaddress\address
\let\d@oldthanks\thanks
\let\d@oldthanksmark\thanksmark
\let\d@oldrunningtitle\runningtitle
\let\d@oldrunningauthors\runningauthors
\let\d@oldmaketitle\maketitle
\let\d@oldfootnote\footnote
\let\d@oldfootnotemark\footnotemark
\let\d@oldfootnotetext\footnotetext

\def\author{\d@ahtitle}
\def\address{\d@ahtitle}
\def\thanks{\d@ahtitle}
\def\thanksmark{\d@ahtitle}
\def\runningtitle{\d@ahtitle}
\def\runningauthors{\d@ahtitle}
\def\maketitle{\d@ahtitle}
\def\footnote{\d@ahmaketitle}
\def\footnotemark{\d@ahmaketitle}
\def\footnotetext{\d@ahmaketitle}

%%**********************************
\endinput