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% This macro source file is from the four volume series
% "TeX in Practice" by Stephan von Bechtolsheim, published
% 1993 by Springer-Verlag, New York.
% Copyright 1993 Stephan von Bechtolsheim.
% No warranty or liability is assumed.
% This macro may be copied freely if no fees other than
% media cost or shipping charges are charged and as long
% as this copyright and the following source code itself
% is not changed. Please see the series for further information.
%
% Version: 1.0
% Date: May 1, 1993
%
%
% This source code is documented in 26.9, p. III-370.
% Original source in file "macros6.TEX", starting line 541.
\wlog{L: "isleapyr.tip" ["macros6.TEX," l. 541, p. III-370]}%
% This file DOES belong to format "texip."
\InputD{imodn.tip}
\catcode`\@ = 11
\newif\if@LeapYear
\def\LeapYearConditional #1{%
    TT\fi
    {%
        \count0 = #1\relax
        \IModN{\count0}{4}{\count1}%
        \ifnum\count1 = 0
            \global\@LeapYeartrue
            \IModN{\count0}{100}{\count2}%
            \IModN{\count0}{400}{\count3}%
            \ifnum\count2 = 0
                \global\@LeapYearfalse
            \fi
            \ifnum\count3 = 0
                \global\@LeapYeartrue
            \fi
        \else
            \global\@LeapYearfalse
        \fi
    }%
    \if@LeapYear
}
\catcode`\@ = 12