% pdflatex
\documentclass[a4paper]{article}
\oddsidemargin=-.2in
\voffset=-1.0in
\parindent=0pt
\usepackage[utf8x]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage[a4paper]{geometry}
\input cprotect-other.tex %For the example of the footnote.

\input Tcode_C.tex
\input Tutils-fastfonts-1.tex %Commenting out this line should not change the output.
%Remove the stretch and shrink of spaces, and the extra space inserted after e.g. a full stop.
%A fixed-wdith font should not have those wider spaces.
\TcodeHook\exP{\the\TcodeHook\frenchspacing}
\CPreParenDefaultMacro %Suppose that unrecognized words preceding a ( are macros
					%The other options are None (the default) and Function

\begin{document}

Some inline code: \ncode{if(x>y*y) test=true; else test=false;}.

%\ident can be used in place of \ncode for single identifiers. It is faster.
The header {\tt stddef.h} defines the macro \ident{NULL}, the type \ident{size_t} and other identifiers.

\begin{Code}
	#include <math.h>
	#include <stdio.h>
	/* ... */
	char *weekday, *month;    // pointers to strings
	int day, hour, min;
	fprintf(stdout, "%s, %s %d, %.2d:%.2d\n",
		  weekday, month, day, hour, min);
	fprintf(stdout, "pi = %.5f\n", 4 * atan(1.0));
\end{Code}

\CodeFramewd=0pt
\DefColor{bkgcolor}{.9, .9, .92}
\CsnippetColor
\def\CsnippetBkg{bkgcolor}

{
\MakeWord{uint}{Typedef}
\MakeWord{Hel2Dg}{Typedef}
\MakeWord{Hel2Dg_pp}{Function}

Using \fcode{}{\\cprotect} to protect a displayed snippet in the argument to \fcode{}{\\footnote}.%
\cprotect\footnote{The following two declarations are equivalent:
\begin{Code}\MakeWord{f}{Function}
float f (float *v, int n);
float f(float v[], int n);
\end{Code}
}

\begin{Code}
#define exfordown(n,third,lineid)    exfordownex(n,third,lineid)
#define exfordownex(n,third,lineid)  for(uint fordown_id##lineid=n; \
							    fordown_id##lineid-- >=1;third)
#define dontimes(n,third)		exfordown(n,third,__LINE__)

Hel2Dg Hel2Dg_pp(const Puntoxy(double)* points1,
		     const Puntoxy(double)* points2, uint n){
	Hel2Dg T;
	const Puntoxy(double) *ptr1, *ptr2;
	double rr1,rr2, c,s;

	T.cg1.y=T.cg1.x=0;
	T.cg2.y=T.cg2.x=0;
	ptr1=points1;
	ptr2=points2;
	dontimes(n,){
		T.cg1.x+=ptr1->x;  T.cg1.y+=ptr1->y;  ptr1++;
		T.cg2.x+=ptr2->x;  T.cg2.y+=ptr2->y;  ptr2++;
	}
	{double aux=1.0/n;
	T.cg1.x*=aux;	T.cg1.y*=aux;
	T.cg2.x*=aux;	T.cg2.y*=aux;}

	rr2=rr1=0;
	s=c=0;
	ptr1=points1;
	ptr2=points2;
	dontimes(n,){
		double x1,y1,x2,y2;
		x1=ptr1->x-T.cg1.x;  y1=ptr1->y-T.cg1.y;  ptr1++;
		x2=ptr2->x-T.cg2.x;  y2=ptr2->y-T.cg2.y;  ptr2++;
		rr1+=x1*x1+y1*y1;
		rr2+=x2*x2+y2*y2;
		c+=x1*x2+y1*y2;
		s+=x1*y2-y1*x2;
	}
	T.esc=sqrt(rr2/rr1);
	{double r=1/sqrt(c*c+s*s);
	T.cosg=c*r;
	T.sing=s*r;}
	return T;
}

#undef exfordown
#undef exfordownex
#undef dontimes
\end{Code}
}

\end{document}

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