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diff --git a/macros/plain/contrib/reverxii/reverxii.tex b/macros/plain/contrib/reverxii/reverxii.tex
index 7877c70ab1..85e5c4ea83 100644
--- a/macros/plain/contrib/reverxii/reverxii.tex
+++ b/macros/plain/contrib/reverxii/reverxii.tex
@@ -1,49 +1,8 @@
-% \iffalse
-\begingroup
- \def\tmp{plain}
- \expandafter
-\endgroup
-\csname if\ifx\tmp\fmtname false\else true\fi\endcsname
- \documentclass{article}
- \usepackage{shortvrb}
- \MakeShortVerb|
- \catcode`\%=9
- \input \jobname.tex
-\fi
-% \fi
-%
-% \title{\texttt{reverxii.tex}\\
-% Playing Reversi in \TeX{}}
-% \author{Bruno Le Floch}
-% \date{December 28, 2011}
-% \newcommand{\cs}[1]{\texttt{\char`\\ #1}}
-% \newcommand{\meta}[1]{$\langle \mathit{#1}\rangle$}
-% \newcommand{\enquote}[1]{``#1''}
-% \makeatletter
-% \def\verbatim{\@verbatim\frenchspacing\@vobeyspaces\catcode`\%=9 \@xverbatim}
-% \makeatother
-% \begin{document}
-% \maketitle
-%
-% \begin{abstract}
-% \texttt{reverxii.tex} is a $938$-byte long \TeX{} program
-% which lets you play Reversi against your favorite typestting engine.
-% To play, run plain \TeX{}, on the command line, in dvi-mode,
-% on the file \texttt{reverxii.tex}. In most distributions,
-% this should mean running \texttt{tex reverxii.tex} in a terminal.
-% To produce the documentation, run \LaTeX{} on the same file,
-% with any engine (\emph{e.g.}, \texttt{pdflatex reverxii.tex}).
-% \end{abstract}
-%
-% \section{The code}
-%
-% Line breaks can be removed, and the stripped down code takes $938$
-% characters.
-% \begin{verbatim}
+\ifx\>\:\documentclass{report}\fi
\vsize5cm\hsize3cm\newlinechar`*\def~#1{\catcode`#113~}
~IJKLMNOPQRSTUVWXYZjqz@.[|](/+^'";:?,_)!*{ 13\def~#1#2{\let#1#2~}
-\def+{\count1}+1=2}*\cr[\ifnum(\ifcase|\or/\else]\fiN\number@\advance
-X\expandafter!\global?\message~\def.#1{@+1 1\countdef#1+1.}
+\def+{\count\ifx\>\:1\fi1}+1=2}*\cr[\ifnum(\ifcase|\or/\else]\fiN\number
+@\advanceX\expandafter!\global?\message~\def.#1{@+1 1\countdef#1+1.}
.IJKLPQRSTUVWYZ.-1P1T2+44P+55P+45T+54T
~j{[0<Q[9>Q[0<J[9>J^/.]/.]/.]/.]}
~^{+NQNJ}~:#1{#11#12#13#14#15#16#17#18}~M#1{?{#1}#1}
@@ -56,328 +15,4 @@ X\expandafter!\global?\message~\def.#1{@+1 1\countdef#1+1.}
~O{Z"Q\multiplyZ3@Z"J@V(Z9|1|6|1|1|2|6|2|4] }~'{M :{&M}&M{*}}
~~{PXTXTNP\halign{&## *M{*}'_1A_2B_3C_4D_5E_6F_7G_8H'}\vfil\break
I1W(W./0] :\AI0 [0<W[1=PQUJL/q])^P;1][.=W?{(RTie/ Player [0>R-/0]
-wins by N[0>R-]R].}X\end]~}~
-% \end{verbatim}
-%
-% To play a two-player game, change |1=P| to |0=P| near the end:
-% this changes the computer player from $0$ to $1$, hence disabling it.
-%
-% \section{Explanation}
-%
-% \subsection{Some comments}
-%
-% The name \texttt{reverxii.tex} is of course a reference to the infamous
-% \texttt{xii.tex}, also on CTAN, which typesets the lyrics of the
-% \textit{Twelve days of Christmas} using code that very few can understand.
-% In my case, I aimed for the shortest possible code, rather than the
-% most obfuscated. In particular, I did not assign weird catcodes
-% other than making most characters active.
-%
-% Since I was aiming for short code, the text presented to the player
-% is concise, but hopefully enough to leave the game understandable
-% and usable. Despite aiming for short code, I thought it would be
-% neat to typeset a record of the game as it goes: after all, \TeX{}
-% is a typesetting program. This used up around $38$ characters, putting
-% me above the $900$ character line.
-%
-% One technique used to make the code shorter is to rename any primitive
-% used more than once into a single active character. Also, counters
-% holding the information about the board are accessed directly by number.
-%
-% A careful reader would notice that changing one of the remaining
-% one-character control sequences to active characters (|$| is still
-% unused) would gain one character. I didn't do it, because it messes
-% up the code-highlighting of my editor |:)|. Of course, I chose the
-% control sequences which are not active characters to be those appearing
-% the least, only twice each.
-%
-% \subsubsection{On with the code!}
-%
-% First set up the page dimensions. This would not be enough for pdf output.
-% \begin{verbatim}
-% \vsize5cm
-% \hsize3cm
-% \end{verbatim}
-%
-% Since plain \TeX{} does not provide the \cs{typeout} command, we are
-% using \cs{message}, hence need to setup a new line character. It is
-% arbitrarily chosen to be |*|, which will be made active and \cs{let}
-% to \cs{cr}.
-% \begin{verbatim}
-% \newlinechar`*
-% \end{verbatim}
-%
-% Then a first loop to make many characters active. The loop ends when
-% reaching the trailing brace group: there we make spaces active, then
-% redefine |~| for the next loop. We still have an annoying |13~| in
-% the input stream. Introduce a short-hand for count registers whose
-% number starts with |1|, then remove |13| by setting |\count11| to
-% |213| (this counter is used for allocation later on). The next loop
-% is triggered by the |~| which we left.
-% \begin{verbatim}
-% \def~#1{\catcode`#113~}
-% ~IJKLMNOPQRSTUVWXYZjqz@.[|](/+^'";:?,_)!*
-% { 13\def~#1#2{\let#1#2~}\def+{\count1}+1=2}
-% \end{verbatim}
-%
-% At this stage, |~| is defined to take two arguments, \cs{let} the
-% first to the second, and repeat. As announced |*| becomes \cs{cr},
-% so that it will be a new line both in messages and in alignments.
-% We try to keep a relatively consistent naming scheme: opening
-% conditionals are left delimiters, \cs{or} and \cs{else} are
-% middle delimiters, and \cs{fi} is a right bracket. Other primitives
-% which are used a lot are also given short names. The loop ends by
-% redefining |~| to \cs{def}.
-% \begin{verbatim}
-% *\cr
-% [\ifnum
-% (\ifcase
-% |\or
-% /\else
-% ]\fi
-% N\number
-% @\advance
-% X\expandafter
-% !\global
-% ?\message
-% ~\def
-% \end{verbatim}
-%
-% It is time to allocate counters. Unfortunately, \cs{newcount}
-% is \cs{outer}, so it is unpractical to use. We have set |+1|,
-% \emph{aka.} |\count11| to $213$, and will allocate counters
-% starting from that number upwards. Repeatedly advance |+1|
-% by $1$ and define the next character to be the counter number |+1|,
-% then repeat. As always, the loop is interrupted by making it
-% redefine the looping macro |.| to be a counter. We use the trailing
-% dot to assign it the value $-1$, then assign a couple of counters:
-% starting player, other player, and the initial position:
-% the squares in rows and columns $4$ and $5$ are initially
-% filled in a cross pattern.
-% \begin{verbatim}
-% .#1{@+1 1\countdef#1+1.}.IJKLPQRSTUVWYZ.-1P1T2+44P+55P+45T+54T
-% \end{verbatim}
-% Let us summarize which counters are used where:
-% \begin{itemize}
-% \item [P] is the current player ($1$ for |-| or $2$ for |0|);
-% \item [T] is the other player;
-% \item [Q] is the row number;
-% \item [J] is the column number;
-% \item [S] is the step size in the row direction;
-% \item [K] is the step size in the column direction;
-% \item [R] is the score difference, positive when $0$ is winning;
-% \item [V] is used when computing the value of placing a piece at
-% the position (|Q|,|J|);
-% \item [W] is the value of the best possible move according to the AI,
-% also used to end the game if neither player can move;
-% \item [U] is the row number of the best move;
-% \item [L] is the column number of the best move;
-% \item [Y] is a boolean, true ($0$) most of the time,
-% it has to do with when we flip or not, but I don't
-% understand it now, help welcome;
-% \item [Z] is a temporary counter, used locally to compute
-% how much a given cell matters (\emph{i.e.} corners are important),
-% and used globally as a boolean to indicate whether to flip pieces
-% or not.
-% \end{itemize}
-%
-% The board is stored in counters |1|\meta{row}\meta{column}.
-% An empty square is has the value $0$, a square for player |-|
-% has value $1$, and player |0| corresponds to the value $2$.
-% The macro |j| retrieves that value, assuming that the row and
-% column numbers are stored as |Q| and |J|, and returns |.|,
-% that is, $-1$, if outside the board. Recall that |[| is \cs{ifnum},
-% |/| is \cs{else}, and |]| is \cs{fi}. When |Q| and |J| are
-% within bounds, the value is retrieved by |^| as
-% |\count1|\meta{row}\meta{column}. Note that |j| and |^| are
-% only safe to use on the left-hand side of an \cs{ifnum} test
-% (because of expansion issues), and that |^| can be used
-% on the left-hand side of an assignment.
-% \begin{verbatim}
-% ~j{[0<Q[9>Q[0<J[9>J^/.]/.]/.]/.]}
-% ~^{+NQNJ}
-% \end{verbatim}
-%
-% We often need to loop over numbers from $1$ to $8$; here is a macro.
-% \begin{verbatim}
-% ~:#1{#11#12#13#14#15#16#17#18}
-% \end{verbatim}
-%
-% The macros to print the board, both to the dvi and to the console.
-% |M| spews its argument as a \cs{message} (|?|), and directly typeset.
-% This is used rather directly to print the first and last lines (|'|),
-% which are simply alignment cells containing each number from $1$ to $8$,
-% with some care given to spaces and new lines.
-% The |_| macro receives a digit and the corresponding capital letter
-% as arguments, and outputs that row of the board. First place the
-% letter on the left of the board, then loop from $1$ to $8$,
-% typesetting and \cs{message}ing a space, |-| or |0|, depending on
-% the value of the relevant count register. Note the two spaces
-% in the definition: the first ends the counter's number, the second
-% is typeset (in plain \TeX{}, active spaces expand to a normal space).
-% \begin{verbatim}
-% ~M#1{?{#1}#1}
-% ~'{M :{&M}&M{*}}
-% ~_#1#2{M#2:{\B#1}&M#2&M{*}}
-% ~\B#1#2{&M{(+#1#2 |-|0]}}
-% \end{verbatim}
-%
-% The input is done by |q|, which queries the user until they give
-% a correct input, so that |Q| and |J| are in the range $[1,8]$.
-% Prompt the user with a small \cs{message}, giving an example
-% of what move he could do (only true at the start, but the hope
-% is that the player will understand what the input format is).
-% The code that follows is similar to \LaTeXe{}'s \cs{@onelevel@sanitize}.
-% We extract the two first characters from the the \cs{meaning}
-% of the user's input (remember, |X| is \cs{expandafter}),
-% as |#2| and |#3| of \cs{D}. Grab the character code of each,
-% relative to the characters |@| (row) or |0| (column).
-% The closing parenthesis is where most of the work is done.
-% It sets |V| to the value of placing a piece in the cell
-% $(|Q|,|J|)$, zero if the move does not flip any of the opponent's
-% pieces, or if the cell is outside the board. After performing
-% that calculation, if |V| is zero, the move was not valid,
-% and we query the user again.
-% \begin{verbatim}
-% ~q{?{Row and column? e.g. E6*}\read.to\EX\D\meaning\E ;}
-% ~\D#1->#2#3#4;{Q`#2@Q-`@J`#3@J-`0)(V?{Invalid move #2#3.}q]}
-% \end{verbatim}
-%
-% So\ldots{} how do we compute the \enquote{value} of a move?
-% It is automatically invalid if |j| does not return $0$:
-% either the cell is occupied, or it is outside the board.
-% Then for each of the $8$ directions around the cell,
-% we count the number of pieces that are flipped in that
-% direction. The direction is stored as two counters,
-% |S| and |K|, each $\pm 1$ or $0$. We call |,| a first
-% time to test whether flipping should happen in that direction,
-% and, if it is (as indicated by the global value of |Z|),
-% call it again to actually flip. The call to |,| must happen
-% within a group, because it directly changes the row and column
-% numbers |Q| and |J|, following which cell is being queried.
-% \begin{verbatim}
-% ~){V0 (jS1z1z0z.S0z1z.S.z1z0z.]}
-% ~z#1{{K#1Z1{Y1,}(Z,]}}
-% \end{verbatim}
-%
-% The macro |,| is recursive. At each step, move $(|Q|,|J|)$
-% in the direction $(|S|,|K|)$. Then, if that cell (|j|)
-% contains a piece belonging to the other player (|T|),
-% do some stuff |(Y!^P!;2]O| and repeat. What is it that
-% we do? Well, if the condition |Y| is met (I don't remember
-% how that works), we set the current cell to belong to the
-% player, globally, and change the score difference by $2$
-% (see |;|), also globally. Then, we compute with |O| the value
-% corresponding to the cell that we might be flipping (see |O|).
-%
-% Otherwise (|/|), if the cell (|j|) contains a piece from the
-% current player (|P|), it means we have reached the end of a
-% run of the form \meta{initial cell} \meta{opponent's pieces}
-% \meta{own piece}, hence the \meta{opponent's pieces} should
-% count as flipped if we place our piece in the \meta{initial
-% cell}. Until there, all changes to |V| were local, returning
-% to the old value at the end of the group that |,| is contained
-% in. Since the run in that direction was successful, we escape
-% the value of |V| from the group with |\global V=V|. Under
-% some conditions, we set the boolean |Z| to true, globally (|!Z0|),
-% which triggers a second call to |,| with different setting,
-% and actually flips the opponent's pieces.
-% \begin{verbatim}
-% ~,{@QS@JK[j=T(Y!^P!;2]O,/[j=P!VV(I(Y/!Z0]]]]}
-% \end{verbatim}
-%
-% I moved those |O| and |"| guys a little bit in this explanation,
-% but not in the original implemenation, because it is hard
-% to sync. We assign weights to each of the $64$ cells:
-% \begin{center}
-% \halign{&\hfil#\hfil\cr
-% 9 & 1 & 6 & 6 & 6 & 6 & 1 & 9 \cr
-% 1 & 1 & 2 & 2 & 2 & 2 & 1 & 9 \cr
-% 6 & 2 & 4 & 4 & 4 & 4 & 2 & 6 \cr
-% 6 & 2 & 4 & 4 & 4 & 4 & 2 & 6 \cr
-% 6 & 2 & 4 & 4 & 4 & 4 & 2 & 6 \cr
-% 6 & 2 & 4 & 4 & 4 & 4 & 2 & 6 \cr
-% 1 & 1 & 2 & 2 & 2 & 2 & 1 & 9 \cr
-% 9 & 1 & 6 & 6 & 6 & 6 & 1 & 9 \cr}
-% \end{center}
-% All weights are positive, so that every move which flips a piece
-% ends up with a positive overall value. The AI would be better if
-% the places next to corners had a negative weight, but I would have
-% too much code to rewrite for that to work. We really have three
-% types of rows and three types of columns. Converting from |Q|
-% or |J| is done by |"|, then we assemble the two as a number
-% in the range $[0,8]$, and use another \cs{ifcase} construction
-% to produce the weights.
-% \begin{verbatim}
-% ~O{Z"Q\multiplyZ3@Z"J@V(Z9|1|6|1|1|2|6|2|4] }
-% ~"#1{(#1|0|1|2|2|2|2|1|0]}
-% \end{verbatim}
-%
-% The counter |R| keeps track of the score difference,
-% and is updated with |;2| (when flipping a piece) or |;1| (when
-% adding a piece). The counter |R| should be \cs{advance}d (|@|)
-% by a positive amount when the current player |P| is player |0|,
-% and a negative amount for player |-|.
-% \begin{verbatim}
-% ~;{@R(P|-]}
-% \end{verbatim}
-%
-% After printing the board, we go through every cell and find the
-% one with the highest value. The macro \cs{A}, does one row, hence
-% |\:\A| does all the rows. Store the argument as the row number |Q|,
-% then loop over columns. After setting the column number |J| to
-% its argument, \cs{C} calls |)|, which as explained above computes
-% the value of placing a piece there, throws away that case if it flips
-% nothing, otherwise also counts the weight of the current cell. Then
-% update the best value |W| and the best row |U| and column |L| if
-% the new |V| is larger than |W|.
-% \begin{verbatim}
-% ~\A#1{Q#1:\C}
-% ~\C#1{J#1)[0<VO[V>WWVUQLJ]]}
-% \end{verbatim}
-%
-% We won't need |~| as \cs{def} anymore, so we reuse it as the main command.
-% \begin{itemize}
-% \item First exchange the players: set |P| equal to |T|, but first expand
-% the value of |P| after |T| to set that as well.
-% \item Secondly, open an alignment, with a repeating preamble adding a space
-% at its end. Then message a new-line (we should be using |?| rather than
-% |M| here, I think) to keep a clean output. Afterwards, print the top line
-% with |'|, the eight lines of the bulk with |_|, and the bottom line,
-% which happens to end with |?{*}*|, \emph{i.e.}, ends with \cs{cr}:
-% we can thus close the alignment, and cause \TeX{} to output the page.
-% \item After printing, it is time to check whether there is a move or not.
-% We don't want to flip pieces at this stage, hence set the boolean |I|
-% to false ($1$). And we reset the best value to $0$, unless it was
-% already $0$ (which means that the previous player had no available
-% move), in which case we set it to $-1$. Then loop over rows, finding
-% the best value (see \cs{A}). Reset the boolean |I| to be true.
-% \item If a move was found in the previous step ($|W|>0$), either
-% use it if the player is the AI, or query the user. The various
-% booleans are set up in such a way as to do the flipping, so
-% calling |)| does it. Then also put a player's piece in the current
-% cell |^|, and increase the score difference by $1$.
-% \item Finally, if neither player could move, declare the game ended,
-% give the score, and \cs{end} the run. Otherwise, repeat.
-% \end{itemize}
-% Of course, after defining |~|, we call it. Let's play!
-% \begin{verbatim}
-% ~~{
-% PXTXTNP
-% \halign{&## *M{*}'_1A_2B_3C_4D_5E_6F_7G_8H'}\vfil\break
-% I1 W(W./0] :\AI0
-% [0<W
-% [1=PQUJL/q]
-% )
-% ^P;1
-% ]
-% [.=W
-% ?{(RTie/ Player [0>R-/0] wins by N[0>R-]R].}
-% X\end
-% ]
-% ~
-% }
-% ~
-% \end{verbatim}
-%
-% \end{document} \ No newline at end of file
+wins by N[0>R-]R].}X\dump]~}~ \ No newline at end of file