% SIG-ALT-RELEASE.CLS - VERSION 1.0

% "COMPATIBLE" WITH THE "ACM_PROC_ARTICLE-SP.CLS" V2.01SP

% PRODUCES A 'TIGHTER' PAPER AND DOES INCLUDE A RELEASE STATEMENT

% Gerald Murray December 6 2000

%

% ---- Start of 'updates' ----

%

% Allowance made to switch default fonts between those systems using

% METAFONT and those using 'Type 1' or 'Truetype' fonts.

% See LINE NUMBER 232 for details.

% Also provided for enumerated/annotated Corollaries 'surrounded' by

% enumerated Theorems (line 790).

% Gerry November 11th. 1999

%

% ---- End of 'updates' ----

%

\def\fileversion{v1.0} % for ACM's tracking purposes

\def\filedate{December 6, 2000} % Gerry Murray's tracking data

\def\docdate {Wednesday 6th. December 2000} % Gerry Murray (with deltas to doc}

\usepackage{epsfig}

\usepackage{amssymb}

\usepackage{amsmath}

\usepackage{amsfonts}

%

% SIG-ALT-RELEASE DOCUMENT STYLE

% G.K.M. Tobin August-October 1999

% adapted from ARTICLE document style by Ken Traub, Olin Shivers

% also using elements of esub2acm.cls

% HEAVILY MODIFIED, SUBSEQUENTLY, BY GERRY MURRAY 2000

% ARTICLE DOCUMENT STYLE -- Released 16 March 1988

% for LaTeX version 2.09

% Copyright (C) 1988 by Leslie Lamport

%

%

%%% sig-alt-release.cls is an 'ALTERNATE-RELEASE' document style for producing

%%% two-column camera-ready pages for ACM conferences.

%%% THIS FILE DOES NOT STRICTLY ADHERE TO THE SIGS (BOARD-ENDORSED)

%%% PROCEEDINGS STYLE. It has been designed to produce a 'tighter'

%%% paper in response to concerns over page budgets.

%%% The main features of this style are:

%%%

%%% 1) Two columns.

%%% 2) Side and top margins of 4.5pc, bottom margin of 6pc, column gutter of

%%% 2pc, hence columns are 20pc wide and 55.5pc tall. (6pc =3D 1in, approx)

%%% 3) First page has title information, and an extra 6pc of space at the

%%% bottom of the first column for the ACM copyright notice.

%%% 4) Text is 9pt on 10pt baselines; titles (except main) are 9pt bold.

%%%

%%%

%%% There are a few restrictions you must observe:

%%%

%%% 1) You cannot change the font size; ACM wants you to use 9pt.

%%% 3) You must start your paper with the \maketitle command. Prior to the

%%% \maketitle you must have \title and \author commands. If you have a

%%% \date command it will be ignored; no date appears on the paper, since

%%% the proceedings will have a date on the front cover.

%%% 4) Marginal paragraphs, tables of contents, lists of figures and tables,

%%% and page headings are all forbidden.

%%% 5) The `figure' environment will produce a figure one column wide; if you

%%% want one that is two columns wide, use `figure*'.

%%%

%

%%% Copyright Space:

%%% This style automatically reserves 1" blank space at the bottom of page 1/

%%% column 1. This space can optionally be filled with some text using the

%%% \toappear{...} command. If used, this command must be BEFORE the \maketitle

%%% command. If this command is defined AND [preprint] is on, then the

%%% space is filled with the {...} text (at the bottom); otherwise, it is

%%% blank. If you use \toappearbox{...} instead of \toappear{...} then a

%%% box will be drawn around the text (if [preprint] is on).

%%%

%%% A typical usage looks like this:

%%% \toappear{To appear in the Ninth AES Conference on Medievil Lithuanian

%%% Embalming Technique, June 1991, Alfaretta, Georgia.}

%%% This will be included in the preprint, and left out of the conference

%%% version.

%%%

%%% WARNING:

%%% Some dvi-ps converters heuristically allow chars to drift from their

%%% true positions a few pixels. This may be noticeable with the 9pt sans-serif

%%% bold font used for section headers.

%%% You may turn this hackery off via the -e option:

%%% dvips -e 0 foo.dvi >foo.ps

%%%

\typeout{Document Class 'sig-alt-release' <6th. December '00>. Modified by G.K.M. Tobin/Gerry Murray}

\typeout{Based in part upon document Style `acmconf' <22 May 89>. Hacked 4/91 by}

\typeout{shivers@cs.cmu.edu, 4/93 by theobald@cs.mcgill.ca}

\typeout{Excerpts were taken from (Journal Style) 'esub2acm.cls'.}

\typeout{****** Bugs/comments/suggestions/technicalities to Gerry Murray -- murray@hq.acm.org ******}

\typeout{Questions on the style, SIGS policies, etc. to Julie Goetz goetz@acm.org or Adrienne Griscti griscti@acm.org}

\oddsidemargin 4.5pc

\evensidemargin 4.5pc

\advance\oddsidemargin by -1in % Correct for LaTeX gratuitousness

\advance\evensidemargin by -1in % Correct for LaTeX gratuitousness

\marginparwidth 0pt % Margin pars are not allowed.

\marginparsep 11pt % Horizontal space between outer margin and

% marginal note

% Top of page:

\topmargin 4.5pc % Nominal distance from top of page to top of

% box containing running head.

\advance\topmargin by -1in % Correct for LaTeX gratuitousness

\headheight 0pt % Height of box containing running head.

\headsep 0pt % Space between running head and text.

% Bottom of page:

\footskip 30pt % Distance from baseline of box containing foot

% to baseline of last line of text.

\@ifundefined{footheight}{\newdimen\footheight}{}% this is for LaTeX2e

\footheight 12pt % Height of box containing running foot.

%% Must redefine the top margin so there's room for headers and

%% page numbers if you are using the preprint option. Footers

%% are OK as is. Olin.

\advance\topmargin by -37pt % Leave 37pt above text for headers

\headheight 12pt % Height of box containing running head.

\headsep 25pt % Space between running head and text.

\textheight 666pt % 9 1/4 column height

\textwidth 42pc % Width of text line.

% For two-column mode:

\columnsep 2pc % Space between columns

\columnseprule 0pt % Width of rule between columns.

\hfuzz 1pt % Allow some variation in column width, otherwise it's

% too hard to typeset in narrow columns.

\footnotesep 5.6pt % Height of strut placed at the beginning of every

% footnote =3D height of normal \footnotesize strut,

% so no extra space between footnotes.

\skip\footins 8.1pt plus 4pt minus 2pt % Space between last line of text and

% top of first footnote.

\floatsep 11pt plus 2pt minus 2pt % Space between adjacent floats moved

% to top or bottom of text page.

\textfloatsep 18pt plus 2pt minus 4pt % Space between main text and floats

% at top or bottom of page.

\intextsep 11pt plus 2pt minus 2pt % Space between in-text figures and

% text.

\@ifundefined{@maxsep}{\newdimen\@maxsep}{}% this is for LaTeX2e

\@maxsep 18pt % The maximum of \floatsep,

% \textfloatsep and \intextsep (minus

% the stretch and shrink).

\dblfloatsep 11pt plus 2pt minus 2pt % Same as \floatsep for double-column

% figures in two-column mode.

\dbltextfloatsep 18pt plus 2pt minus 4pt% \textfloatsep for double-column

% floats.

\@ifundefined{@dblmaxsep}{\newdimen\@dblmaxsep}{}% this is for LaTeX2e

\@dblmaxsep 18pt % The maximum of \dblfloatsep and

% \dbltexfloatsep.

\@fptop 0pt plus 1fil % Stretch at top of float page/column. (Must be

% 0pt plus ...)

\@fpsep 8pt plus 2fil % Space between floats on float page/column.

\@fpbot 0pt plus 1fil % Stretch at bottom of float page/column. (Must be

% 0pt plus ... )

\@dblfptop 0pt plus 1fil % Stretch at top of float page. (Must be 0pt plus ...)

\@dblfpsep 8pt plus 2fil % Space between floats on float page.

\@dblfpbot 0pt plus 1fil % Stretch at bottom of float page. (Must be

% 0pt plus ... )

\marginparpush 5pt % Minimum vertical separation between two marginal

% notes.

\parskip 0pt plus 1pt % Extra vertical space between paragraphs.

\parindent 9pt % GM July 2000 / was 0pt - width of paragraph indentation.

\partopsep 2pt plus 1pt minus 1pt% Extra vertical space, in addition to

% \parskip and \topsep, added when user

% leaves blank line before environment.

\@lowpenalty 51 % Produced by \nopagebreak[1] or \nolinebreak[1]

\@medpenalty 151 % Produced by \nopagebreak[2] or \nolinebreak[2]

\@highpenalty 301 % Produced by \nopagebreak[3] or \nolinebreak[3]

\@beginparpenalty -\@lowpenalty % Before a list or paragraph environment.

\@endparpenalty -\@lowpenalty % After a list or paragraph environment.

\@itempenalty -\@lowpenalty % Between list items.

\@namedef{ds@10pt}{\@latexerr{The `10pt' option is not allowed in the `acmconf'

document style.}\@eha}

\@namedef{ds@11pt}{\@latexerr{The `11pt' option is not allowed in the `acmconf'

document style.}\@eha}

\@namedef{ds@12pt}{\@latexerr{The `12pt' option is not allowed in the `acmconf'

document style.}\@eha}

\@options

\lineskip 2pt % \lineskip is 1pt for all font sizes.

\normallineskip 2pt

\def\baselinestretch{1}

\abovedisplayskip 9pt plus2pt minus4.5pt%

\belowdisplayskip \abovedisplayskip

\abovedisplayshortskip \z@ plus3pt%

\belowdisplayshortskip 5.4pt plus3pt minus3pt%

\let\@listi\@listI % Setting of \@listi added 9 Jun 87

\def\small{\@setsize\small{9pt}\viiipt\@viiipt

\abovedisplayskip 7.6pt plus 3pt minus 4pt%

\belowdisplayskip \abovedisplayskip

\abovedisplayshortskip \z@ plus2pt%

\belowdisplayshortskip 3.6pt plus2pt minus 2pt

\def\@listi{\leftmargin\leftmargini %% Added 22 Dec 87

\topsep 4pt plus 2pt minus 2pt\parsep 2pt plus 1pt minus 1pt

\itemsep \parsep}}

\def\footnotesize{\@setsize\footnotesize{9pt}\ixpt\@ixpt

\abovedisplayskip 6.4pt plus 2pt minus 4pt%

\belowdisplayskip \abovedisplayskip

\abovedisplayshortskip \z@ plus 1pt%

\belowdisplayshortskip 2.7pt plus 1pt minus 2pt

\def\@listi{\leftmargin\leftmargini %% Added 22 Dec 87

\topsep 3pt plus 1pt minus 1pt\parsep 2pt plus 1pt minus 1pt

\itemsep \parsep}}

\newcount\aucount

\newcount\originalaucount

\newdimen\auwidth

\auwidth=\textwidth

\newdimen\auskip

\newcount\auskipcount

\newdimen\auskip

\global\auskip=1pc

\newdimen\allauboxes

\allauboxes=\auwidth

\newtoks\addauthors

\newcount\addauflag

\global\addauflag=0 %Haven't shown additional authors yet

\newtoks\subtitletext

\gdef\subtitle#1{\subtitletext={#1}}

\gdef\additionalauthors#1{\addauthors={#1}}

\gdef\numberofauthors#1{\global\aucount=#1

\ifnum\aucount>3\global\originalaucount=\aucount \global\aucount=3\fi %g}

\global\auskipcount=\aucount\global\advance\auskipcount by 1

\global\multiply\auskipcount by 2

\global\multiply\auskip by \auskipcount

\global\advance\auwidth by -\auskip

\global\divide\auwidth by \aucount}

% \and was modified to count the number of authors. GKMT 12 Aug 1999

\def\alignauthor{% % \begin{tabular}

\end{tabular}%

\begin{tabular}[t]{p{\auwidth}}\centering}%

% *** NOTE *** NOTE *** NOTE *** NOTE ***

% If you have 'font problems' then you may need

% to change these, e.g. 'arialb' instead of "arialbd".

% Gerry Murray 11/11/1999

% *** OR ** comment out block A and activate block B or vice versa.

% **********************************************

%

% -- Start of block A -- (Type 1 or Truetype fonts)

%\newfont{\secfnt}{timesbd at 12pt} % was timenrb originally - now is timesbd

%\newfont{\secit}{timesbi at 12pt} %13 Jan 00 gkmt

%\newfont{\subsecfnt}{timesi at 11pt} % was timenrri originally - now is timesi

%\newfont{\subsecit}{timesbi at 11pt} % 13 Jan 00 gkmt -- was times changed to timesbi gm 2/4/2000

% % because "normal" is italic, "italic" is Roman

%\newfont{\ttlfnt}{arialbd at 18pt} % was arialb originally - now is arialbd

%\newfont{\ttlit}{arialbi at 18pt} % 13 Jan 00 gkmt

%\newfont{\subttlfnt}{arial at 14pt} % was arialr originally - now is arial

%\newfont{\subttlit}{ariali at 14pt} % 13 Jan 00 gkmt

%\newfont{\subttlbf}{arialbd at 14pt} % 13 Jan 00 gkmt

%\newfont{\aufnt}{arial at 12pt} % was arialr originally - now is arial

%\newfont{\auit}{ariali at 12pt} % 13 Jan 00 gkmt

%\newfont{\affaddr}{arial at 10pt} % was arialr originally - now is arial

%\newfont{\affaddrit}{ariali at 10pt} %13 Jan 00 gkmt

%\newfont{\eaddfnt}{arial at 12pt} % was arialr originally - now is arial

%\newfont{\ixpt}{times at 9pt} % was timenrr originally - now is times

%\newfont{\confname}{timesi at 8pt} % was timenrri - now is timesi

%\newfont{\crnotice}{times at 8pt} % was timenrr originally - now is times

%\newfont{\ninept}{times at 9pt} % was timenrr originally - now is times

% *********************************************

% -- End of block A --

%

%

% -- Start of block B -- METAFONT

% +++++++++++++++++++++++++++++++++++++++++++++

% Next (default) block for those using Metafont

% Gerry Murray 11/11/1999

% *** THIS BLOCK FOR THOSE USING METAFONT *****

% *********************************************

\newfont{\secfnt}{ptmb at 12pt}

\newfont{\secit}{ptmbi at 12pt} %13 Jan 00 gkmt

\newfont{\subsecfnt}{ptmri at 11pt}

\newfont{\subsecit}{ptmbi at 11pt} % 13 Jan 00 gkmt -- was ptmr changed to ptmbi gm 2/4/2000

% because "normal" is italic, "italic" is Roman

\newfont{\ttlfnt}{phvb at 18pt}

\newfont{\ttlit}{phvbo at 18pt} % GM 2/4/2000

\newfont{\subttlfnt}{phvr at 14pt}

\newfont{\subttlit}{phvro at 14pt} % GM 2/4/2000

\newfont{\subttlbf}{phvb at 14pt} % 13 Jan 00 gkmt

\newfont{\aufnt}{phvr at 12pt}

\newfont{\auit}{phvro at 12pt} % GM 2/4/2000

\newfont{\affaddr}{phvr at 10pt}

\newfont{\affaddrit}{phvro at 10pt} % GM 2/4/2000

\newfont{\eaddfnt}{phvr at 12pt}

\newfont{\ixpt}{ptmr at 9pt}

\newfont{\confname}{ptmri at 8pt}

\newfont{\crnotice}{ptmr at 8pt}

\newfont{\ninept}{ptmr at 9pt}

% +++++++++++++++++++++++++++++++++++++++++++++

% -- End of block B --

\def\email#1{{{\eaddfnt{\vskip 4pt#1}}}}

\def\addauthorsection{\ifnum\originalaucount>3

\section{Additional Authors}\the\addauthors

\fi}

\newcount\savesection

\newcount\sectioncntr

\global\sectioncntr=1

\setcounter{secnumdepth}{3}

\def\appendix{\par

\section*{APPENDIX}

\setcounter{section}{0}

\setcounter{subsection}{0}

\def\thesection{\Alph{section}} }

\leftmargini 22.5pt

\leftmarginii 19.8pt % > \labelsep + width of '(m)'

\leftmarginiii 16.8pt % > \labelsep + width of 'vii.'

\leftmarginiv 15.3pt % > \labelsep + width of 'M.'

\leftmarginv 9pt

\leftmarginvi 9pt

\leftmargin\leftmargini

\labelsep 4.5pt

\labelwidth\leftmargini\advance\labelwidth-\labelsep

\def\@listI{\leftmargin\leftmargini \parsep 3.6pt plus 2pt minus 1pt%

\topsep 7.2pt plus 2pt minus 4pt%

\itemsep 3.6pt plus 2pt minus 1pt}

\let\@listi\@listI

\@listi

\def\@listii{\leftmargin\leftmarginii

\labelwidth\leftmarginii\advance\labelwidth-\labelsep

\topsep 3.6pt plus 2pt minus 1pt

\parsep 1.8pt plus 0.9pt minus 0.9pt

\itemsep \parsep}

\def\@listiii{\leftmargin\leftmarginiii

\labelwidth\leftmarginiii\advance\labelwidth-\labelsep

\topsep 1.8pt plus 0.9pt minus 0.9pt

\parsep \z@ \partopsep 1pt plus 0pt minus 1pt

\itemsep \topsep}

\def\@listiv{\leftmargin\leftmarginiv

\labelwidth\leftmarginiv\advance\labelwidth-\labelsep}

\def\@listv{\leftmargin\leftmarginv

\labelwidth\leftmarginv\advance\labelwidth-\labelsep}

\def\@listvi{\leftmargin\leftmarginvi

\labelwidth\leftmarginvi\advance\labelwidth-\labelsep}

\def\labelenumi{\theenumi.}

\def\theenumi{\arabic{enumi}}

\def\labelenumii{(\theenumii)}

\def\theenumii{\alph{enumii}}

\def\p@enumii{\theenumi}

\def\labelenumiii{\theenumiii.}

\def\theenumiii{\roman{enumiii}}

\def\p@enumiii{\theenumi(\theenumii)}

\def\labelenumiv{\theenumiv.}

\def\theenumiv{\Alph{enumiv}}

\def\p@enumiv{\p@enumiii\theenumiii}

\def\labelitemi{$\bullet$}

\def\labelitemii{\bf --}

\def\labelitemiii{$\ast$}

\def\labelitemiv{$\cdot$}

\def\verse{\let\\=\@centercr

\list{}{\itemsep\z@ \itemindent -1.5em\listparindent \itemindent

\rightmargin\leftmargin\advance\leftmargin 1.5em}\item[]}

\let\endverse\endlist

\def\quotation{\list{}{\listparindent 1.5em

\itemindent\listparindent

\rightmargin\leftmargin \parsep 0pt plus 1pt}\item[]}

\let\endquotation=\endlist

\def\quote{\list{}{\rightmargin\leftmargin}\item[]}

\let\endquote=\endlist

\def\descriptionlabel#1{\hspace\labelsep \bf #1}

\def\description{\list{}{\labelwidth\z@ \itemindent-\leftmargin

\let\makelabel\descriptionlabel}}

\let\enddescription\endlist

\def\theequation{\arabic{equation}}

\arraycolsep 4.5pt % Half the space between columns in an array environment.

\tabcolsep 5.4pt % Half the space between columns in a tabular environment.

\arrayrulewidth .4pt % Width of rules in array and tabular environment.

\doublerulesep 1.8pt % Space between adjacent rules in array or tabular env.

\tabbingsep \labelsep % Space used by the \' command. (See LaTeX manual.)

\skip\@mpfootins =\skip\footins

\fboxsep =2.7pt % Space left between box and text by \fbox and \framebox.

\fboxrule =.4pt % Width of rules in box made by \fbox and \framebox.

\def\thepart{\Roman{part}} % Roman numeral part numbers.

\def\thesection {\arabic{section}}

\def\thesubsection {\thesection.\arabic{subsection}}

\def\thesubsubsection {\thesubsection.\arabic{subsubsection}}

\def\theparagraph {\thesubsubsection.\arabic{paragraph}}

\def\thesubparagraph {\theparagraph.\arabic{subparagraph}}

\def\@pnumwidth{1.55em}

\def\@tocrmarg {2.55em}

\def\@dotsep{4.5}

\setcounter{tocdepth}{3}

\def\tableofcontents{\@latexerr{\tableofcontents: Tables of contents are not

allowed in the `acmconf' document style.}\@eha}

\def\l@part#1#2{\addpenalty{\@secpenalty}

\addvspace{2.25em plus 1pt} % space above part line

\begingroup

\@tempdima 3em % width of box holding part number, used by

\parindent \z@ \rightskip \@pnumwidth %% \numberline

\parfillskip -\@pnumwidth

{\large \bf % set line in \large boldface

\leavevmode % TeX command to enter horizontal mode.

#1\hfil \hbox to\@pnumwidth{\hss #2}}\par

\nobreak % Never break after part entry

\endgroup}

\def\l@section#1#2{\addpenalty{\@secpenalty} % good place for page break

\addvspace{1.0em plus 1pt} % space above toc entry

\@tempdima 1.5em % width of box holding section number

\begingroup

\parindent \z@ \rightskip \@pnumwidth

\parfillskip -\@pnumwidth

\bf % Boldface.

\leavevmode % TeX command to enter horizontal mode.

\advance\leftskip\@tempdima %% added 5 Feb 88 to conform to

\hskip -\leftskip %% 25 Jan 88 change to \numberline

#1\nobreak\hfil \nobreak\hbox to\@pnumwidth{\hss #2}\par

\endgroup}

\def\l@subsection{\@dottedtocline{2}{1.5em}{2.3em}}

\def\l@subsubsection{\@dottedtocline{3}{3.8em}{3.2em}}

\def\l@paragraph{\@dottedtocline{4}{7.0em}{4.1em}}

\def\l@subparagraph{\@dottedtocline{5}{10em}{5em}}

\def\listoffigures{\@latexerr{\listoffigures: Lists of figures are not

allowed in the `acmconf' document style.}\@eha}

\def\l@figure{\@dottedtocline{1}{1.5em}{2.3em}}

\def\listoftables{\@latexerr{\listoftables: Lists of tables are not

allowed in the `acmconf' document style.}\@eha}

\let\l@table\l@figure

\def\footnoterule{\kern-3\p@

\hrule width .4\columnwidth

\kern 2.6\p@} % The \hrule has default height of .4pt .

\long\def\@makefntext#1{\noindent

\hbox to .5em{\hss$^{\@thefnmark}$}#1}

\long\def\@maketntext#1{\noindent

#1}

\long\def\@maketitlenotetext#1#2{\noindent

\hbox to 1.8em{\hss$^{#1}$}#2}

\setcounter{topnumber}{2}

\def\topfraction{.7}

\setcounter{bottomnumber}{1}

\def\bottomfraction{.3}

\setcounter{totalnumber}{3}

\def\textfraction{.2}

\def\floatpagefraction{.5}

\setcounter{dbltopnumber}{2}

\def\dbltopfraction{.7}

\def\dblfloatpagefraction{.5}

%

\long\def\@makecaption#1#2{

\vskip \baselineskip

\setbox\@tempboxa\hbox{\textbf{#1: #2}}

\ifdim \wd\@tempboxa >\hsize % IF longer than one line:

\textbf{#1: #2}\par % THEN set as ordinary paragraph.

\else % ELSE center.

\hbox to\hsize{\hfil\box\@tempboxa\hfil}\par

\fi}

%

\long\def\@makecaption#1#2{

\vskip 10pt

\setbox\@tempboxa\hbox{\textbf{#1: #2}}

\ifdim \wd\@tempboxa >\hsize % IF longer than one line:

\textbf{#1: #2}\par % THEN set as ordinary paragraph.

\else % ELSE center.

\hbox to\hsize{\hfil\box\@tempboxa\hfil}

\fi}

\@ifundefined{figure}{\newcounter {figure}} % this is for LaTeX2e

\def\fps@figure{tbp}

\def\ftype@figure{1}

\def\ext@figure{lof}

\def\fnum@figure{Figure \thefigure}

\def\figure{\@float{figure}}

\let\endfigure\end@float

\@namedef{figure*}{\@dblfloat{figure}}

\@namedef{endfigure*}{\end@dblfloat}

\@ifundefined{table}{\newcounter {table}} % this is for LaTeX2e

\def\fps@table{tbp}

\def\ftype@table{2}

\def\ext@table{lot}

\def\fnum@table{Table \thetable}

\def\table{\@float{table}}

\let\endtable\end@float

\@namedef{table*}{\@dblfloat{table}}

\@namedef{endtable*}{\end@dblfloat}

\newtoks\titleboxnotes

\newcount\titleboxnoteflag

\def\maketitle{\par

\begingroup

\def\thefootnote{\fnsymbol{footnote}}

\def\@makefnmark{\hbox

to 0pt{$^{\@thefnmark}$\hss}}

\twocolumn[\@maketitle]

\@thanks

\endgroup

\setcounter{footnote}{0}

\let\maketitle\relax

\let\@maketitle\relax

\gdef\@thanks{}\gdef\@author{}\gdef\@title{}\gdef\@subtitle{}\let\thanks\relax

\@copyrightspace}

%% CHANGES ON NEXT LINES

\newif\if@ll % to record which version of LaTeX is in use

\expandafter\ifx\csname LaTeXe\endcsname\relax % LaTeX2.09 is used

\else% LaTeX2e is used, so set ll to true

\global\@lltrue

\fi

\if@ll

\NeedsTeXFormat{LaTeX2e}

\ProvidesClass{sig-alt-release} [2000/12/06 - V1.0 - based on acmproc.cls V1.3 <Nov. 30 '99>]

\RequirePackage{latexsym}% QUERY: are these two really needed?

\let\dooptions\ProcessOptions

\else

\let\dooptions\@options

\fi

%% END CHANGES

\def\@height{height}

\def\@width{width}

\def\@minus{minus}

\def\@plus{plus}

\def\hb@xt@{\hbox to}

\newif\if@faircopy

\@faircopyfalse

\def\ds@faircopy{\@faircopytrue}

\def\ds@preprint{\@faircopyfalse}

\@twosidetrue

\@mparswitchtrue

\def\ds@draft{\overfullrule 5\p@}

%% CHANGE ON NEXT LINE

\dooptions

\lineskip \p@

\normallineskip \p@

\def\baselinestretch{1}

\def\@ptsize{0} %needed for amssymbols.sty

%% CHANGES ON NEXT LINES

\if@ll% allow use of old-style font change commands in LaTeX2e

\@maxdepth\maxdepth

%

\DeclareOldFontCommand{\rm}{\ninept\rmfamily}{\mathrm}

\DeclareOldFontCommand{\sf}{\normalfont\sffamily}{\mathsf}

\DeclareOldFontCommand{\tt}{\normalfont\ttfamily}{\mathtt}

\DeclareOldFontCommand{\bf}{\normalfont\bfseries}{\mathbf}

\DeclareOldFontCommand{\it}{\normalfont\itshape}{\mathit}

\DeclareOldFontCommand{\sl}{\normalfont\slshape}{\@nomath\sl}

\DeclareOldFontCommand{\sc}{\normalfont\scshape}{\@nomath\sc}

\DeclareRobustCommand*{\cal}{\@fontswitch{\relax}{\mathcal}}

\DeclareRobustCommand*{\mit}{\@fontswitch{\relax}{\mathnormal}}

\fi

%

\if@ll

\renewcommand{\rmdefault}{cmr} % was 'ttm'

% Note! I have also found 'mvr' to work ESPECIALLY well.

% Gerry - October 1999

% You may need to change your LV1times.fd file so that sc is

% mapped to cmcsc - -for smallcaps -- that is if you decide

% to change {cmr} to {times} above. (Not recommended)

\renewcommand{\@ptsize}{}

\renewcommand{\normalsize}{%

\@setfontsize\normalsize\@ixpt{10.5\p@}%\ninept%

\abovedisplayskip 6\p@ \@plus2\p@ \@minus\p@

\belowdisplayskip \abovedisplayskip

\abovedisplayshortskip 6\p@ \@minus 3\p@

\belowdisplayshortskip 6\p@ \@minus 3\p@

\let\@listi\@listI

}

\else

\def\@normalsize{%changed next to 9 from 10

\@setsize\normalsize{9\p@}\ixpt\@ixpt

\abovedisplayskip 6\p@ \@plus2\p@ \@minus\p@

\belowdisplayskip \abovedisplayskip

\abovedisplayshortskip 6\p@ \@minus 3\p@

\belowdisplayshortskip 6\p@ \@minus 3\p@

\let\@listi\@listI

}%

\fi

\if@ll

\newcommand\scriptsize{\@setfontsize\scriptsize\@viipt{8\p@}}

\newcommand\tiny{\@setfontsize\tiny\@vpt{6\p@}}

\newcommand\large{\@setfontsize\large\@xiipt{14\p@}}

\newcommand\Large{\@setfontsize\Large\@xivpt{18\p@}}

\newcommand\LARGE{\@setfontsize\LARGE\@xviipt{20\p@}}

\newcommand\huge{\@setfontsize\huge\@xxpt{25\p@}}

\newcommand\Huge{\@setfontsize\Huge\@xxvpt{30\p@}}

\else

\def\scriptsize{\@setsize\scriptsize{8\p@}\viipt\@viipt}

\def\tiny{\@setsize\tiny{6\p@}\vpt\@vpt}

\def\large{\@setsize\large{14\p@}\xiipt\@xiipt}

\def\Large{\@setsize\Large{18\p@}\xivpt\@xivpt}

\def\LARGE{\@setsize\LARGE{20\p@}\xviipt\@xviipt}

\def\huge{\@setsize\huge{25\p@}\xxpt\@xxpt}

\def\Huge{\@setsize\Huge{30\p@}\xxvpt\@xxvpt}

\fi

\normalsize

% make aubox hsize/number of authors up to 3, less gutter

% then showbox gutter showbox gutter showbox -- GKMT Aug 99

\newbox\@acmtitlebox

\def\@maketitle{\newpage

\null

\setbox\@acmtitlebox\vbox{%

\baselineskip 20pt

\vskip 2em % Vertical space above title.

\begin{center}

{\ttlfnt \@title\par} % Title set in 18pt Helvetica (Arial) bold size.

\vskip 1.5em % Vertical space after title.

%This should be the subtitle.

{\subttlfnt \the\subtitletext\par}\vskip 1.25em%\fi

{\baselineskip 16pt\aufnt % each author set in \12 pt Arial, in a

\lineskip .5em % tabular environment

\begin{tabular}[t]{c}\@author

\end{tabular}\par}

\vskip 1.5em % Vertical space after author.

\end{center}}

\dimen0=\ht\@acmtitlebox

\advance\dimen0 by -12.75pc\relax % Increased space for title box -- KBT

\unvbox\@acmtitlebox

\ifdim\dimen0<0.0pt\relax\vskip-\dimen0\fi}

\newcount\titlenotecount

\global\titlenotecount=0

\newtoks\tntoks

\newtoks\tntokstwo

\newtoks\tntoksthree

\newtoks\tntoksfour

\newtoks\tntoksfive

\def\abstract{

\ifnum\titlenotecount>0 % was =1

\insert\footins{%

\reset@font\footnotesize

\interlinepenalty\interfootnotelinepenalty

\splittopskip\footnotesep

\splitmaxdepth \dp\strutbox \floatingpenalty \@MM

\hsize\columnwidth \@parboxrestore

\protected@edef\@currentlabel{%

}%

\color@begingroup

\ifnum\titlenotecount=1

\@maketntext{%

\raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\@finalstrut\strutbox}%

\fi

\ifnum\titlenotecount=2

\@maketntext{%

\raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\@finalstrut\strutbox}%

\fi

\ifnum\titlenotecount=3

\@maketntext{%

\raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\@finalstrut\strutbox}%

\fi

\ifnum\titlenotecount=4

\@maketntext{%

\raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\S$}\rule\z@\footnotesep\ignorespaces\the\tntoksfour\@finalstrut\strutbox}%

\fi

\ifnum\titlenotecount=5

\@maketntext{%

\raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\S$}\rule\z@\footnotesep\ignorespaces\the\tntoksfour\par\@finalstrut\strutbox}%

\@maketntext{%

\raisebox{4pt}{$\P$}\rule\z@\footnotesep\ignorespaces\the\tntoksfive\@finalstrut\strutbox}%

\fi

\color@endgroup} %g}

\fi

\setcounter{footnote}{0}

\section*{ABSTRACT}\normalsize%\ninept

}

\def\endabstract{\if@twocolumn\else\endquotation\fi}

\def\keywords{\if@twocolumn

\section*{Keywords}

\else \small

\quotation

\fi}

\def\terms{\if@twocolumn

\section*{General Terms}

\else \small

\quotation

\fi}

% -- Classification needs to be a bit smart due to optionals - Gerry/Georgia November 2nd. 1999

\newcount\catcount

\global\catcount=1

\def\category#1#2#3{%

\ifnum\catcount=1

\section*{Categories and Subject Descriptors}

\advance\catcount by 1\else{\unskip; }\fi

\@ifnextchar [{\@category{#1}{#2}{#3}}{\@category{#1}{#2}{#3}[]}%

}

\def\@category#1#2#3[#4]{%

\begingroup

\let\and\relax

#1 [\textbf{#2}]%

\if!#4!%

\if!#3!\else : #3\fi

\else

:\space

\if!#3!\else #3\kern\z@---\hskip\z@\fi

\textit{#4}%

\fi

\endgroup

}

%

%%% This section (written by KBT) handles the 1" box in the lower left

%%% corner of the left column of the first page by creating a picture,

%%% and inserting the predefined string at the bottom (with a negative

%%% displacement to offset the space allocated for a non-existent

%%% caption).

%%%

\newtoks\copyrightnotice

\def\ftype@copyrightbox{8}

\def\@copyrightspace{

\@float{copyrightbox}[b]

\begin{center}

\setlength{\unitlength}{1pc}

%\begin{picture}(20,6) %Space for copyright notice

\begin{picture}(20,1) %Space for copyright notice

\put(0,-0.95){\crnotice{\@toappear}}

\end{picture}

\end{center}

\end@float}

\def\@toappear{} % Default setting blank - commands below change this.

\long\def\toappear#1{\def\@toappear{\parbox[b]{20pc}{\baselineskip 9pt#1}}}

\def\toappearbox#1{\def\@toappear{\raisebox{5pt}{\framebox[20pc]{\parbox[b]{19pc}{#1}}}}}

\newtoks\conf

\newtoks\confinfo

\def\conferenceinfo#1#2{\global\conf={#1}\global\confinfo{#2}}

\def\marginpar{\@latexerr{The \marginpar command is not allowed in the

`acmconf' document style.}\@eha}

\mark{{}{}} % Initializes TeX's marks

\def\today{\ifcase\month\or

January\or February\or March\or April\or May\or June\or

July\or August\or September\or October\or November\or December\fi

\space\number\day, \number\year}

\def\@begintheorem#1#2{%

\parskip 0pt % GM July 2000 (for tighter spacing)

\trivlist

\item[%

\hskip 10\p@

\hskip \labelsep

{{\sc #1}\hskip 5\p@\relax#2.}%

]

\it

}

\def\@opargbegintheorem#1#2#3{%

\parskip 0pt % GM July 2000 (for tighter spacing)

\trivlist

\item[%

\hskip 10\p@

\hskip \labelsep

{\sc #1\ #2\ % This mod by Gerry to enumerate corollaries

\setbox\@tempboxa\hbox{(#3)} % and bracket the 'corollary title'

\ifdim \wd\@tempboxa>\z@ % and retain the correct numbering of e.g. theorems

\hskip 5\p@\relax % if they occur 'around' said corollaries.

\box\@tempboxa % Gerry - Nov. 1999.

\fi.}%

]

\it

}

\newif\if@qeded

\global\@qededfalse

\def\proof{%

\vspace{-\parskip} % GM July 2000 (for tighter spacing)

\global\@qededfalse

\@ifnextchar[{\@xproof}{\@proof}%

}

\def\endproof{%

\if@qeded\else\qed\fi

\endtrivlist

}

\def\@proof{%

\trivlist

\item[%

\hskip 10\p@

\hskip \labelsep

{\sc Proof.}%

]

\ignorespaces

}

\def\@xproof[#1]{%

\trivlist

\item[\hskip 10\p@\hskip \labelsep{\sc Proof #1.}]%

\ignorespaces

}

\def\qed{%

\unskip

\kern 10\p@

\begingroup

\unitlength\p@

\linethickness{.4\p@}%

\framebox(6,6){}%

\endgroup

\global\@qededtrue

}

\def\newdef#1#2{%

\expandafter\@ifdefinable\csname #1\endcsname

{\@definecounter{#1}%

\expandafter\xdef\csname the#1\endcsname{\@thmcounter{#1}}%

\global\@namedef{#1}{\@defthm{#1}{#2}}%

\global\@namedef{end#1}{\@endtheorem}%

}%

}

\def\@defthm#1#2{%

\refstepcounter{#1}%

\@ifnextchar[{\@ydefthm{#1}{#2}}{\@xdefthm{#1}{#2}}%

}

\def\@xdefthm#1#2{%

\@begindef{#2}{\csname the#1\endcsname}%

\ignorespaces

}

\def\@ydefthm#1#2[#3]{%

\trivlist

\item[%

\hskip 10\p@

\hskip \labelsep

{\it #2%

\savebox\@tempboxa{#3}%

\ifdim \wd\@tempboxa>\z@

\ \box\@tempboxa

\fi.%

}]%

\ignorespaces

}

\def\@begindef#1#2{%

\trivlist

\item[%

\hskip 10\p@

\hskip \labelsep

{\it #1\ \rm #2.}%

]%

}

\def\theequation{\arabic{equation}}

\newcounter{part}

\newcounter{section}

\newcounter{subsection}[section]

\newcounter{subsubsection}[subsection]

\newcounter{paragraph}[subsubsection]

\def\thepart{\Roman{part}}

\def\thesection{\arabic{section}}

\def\thesubsection{\thesection.\arabic{subsection}}

\def\thesubsubsection{{\subsecfnt\thesubsection.\arabic{subsubsection}}}

\def\theparagraph{{\subsecfnt\thesubsubsection.\arabic{paragraph}}}

\newif\if@uchead

\@ucheadfalse

%% CHANGES: NEW NOTE

%% NOTE: OK to use old-style font commands below, since they were

%% suitably redefined for LaTeX2e

%% END CHANGES

\setcounter{secnumdepth}{3}

\def\part{%

\@startsection{part}{9}{\z@}{-10\p@ \@plus -4\p@ \@minus -2\p@}

{4\p@}{\normalsize\@ucheadtrue}%

}

\def\section{%

\@startsection{section}{1}{\z@}{-10\p@ \@plus -4\p@ \@minus -2\p@}% GM

{4\p@}{\baselineskip 14pt\secfnt\@ucheadtrue}%

}

\def\subsection{%

\@startsection{subsection}{2}{\z@}{-8\p@ \@plus -2\p@ \@minus -\p@}

{4\p@}{\secfnt}%

}

\def\subsubsection{%

\@startsection{subsubsection}{3}{\z@}{-8\p@ \@plus -2\p@ \@minus -\p@}%

{4\p@}{\subsecfnt}%

}

\def\paragraph{%

\vskip 12pt\@startsection{paragraph}{3}{\z@}{6\p@ \@plus \p@}%

{-5\p@}{\subsecfnt}%

}

\let\@period=.

\def\@startsection#1#2#3#4#5#6{%

\if@noskipsec %gkmt, 11 aug 99

\global\let\@period\@empty

\leavevmode

\global\let\@period.%

\fi

\par %

\@tempskipa #4\relax

\@afterindenttrue

\ifdim \@tempskipa <\z@

\@tempskipa -\@tempskipa

\@afterindentfalse

\fi

\if@nobreak

\everypar{}%

\else

\addpenalty\@secpenalty

\addvspace\@tempskipa

\fi

\parskip=0pt % GM July 2000 (non numbered) section heads

\@ifstar

{\@ssect{#3}{#4}{#5}{#6}}

{\@dblarg{\@sect{#1}{#2}{#3}{#4}{#5}{#6}}}%

}

\def\@sect#1#2#3#4#5#6[#7]#8{%

\ifnum #2>\c@secnumdepth

\let\@svsec\@empty

\else

\refstepcounter{#1}%

\edef\@svsec{%

\begingroup

\ifnum#2>2 \noexpand\rm \fi

\csname the#1\endcsname

\endgroup

\ifnum #2=1\relax .\fi

\hskip 1em

}%

\fi

\@tempskipa #5\relax

\ifdim \@tempskipa>\z@