#include <stdio.h>



int c;

FILE *in, *out;



/* #define out stdout */



#define output(str) fprintf (out, "%s", str)



char *ptr = NULL;



int next_char ()

{

    if (ptr == NULL || *ptr == 0)

	return fgetc (in);

    /* printf ("0x%X\n", ptr); */

    return *ptr++;   

}



scan_word (char *buf)

{

int i;

		i = 0;

		for (;;)

		{

		    /* buf[i++] = c; */

		    buf[i++] = c;

		    c = next_char ();

		    if (! ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z')))

			break; 

		}

		buf[i] = 0;

}



scan_expr ()

{

char buf[1000];

char buf_out[2000];

int i;    

int status;

        if (c == EOF)

	    return 0;

        switch (c)

	{

	    case '_':

		output ("<sub>");

		c = next_char ();

		scan_expr ();

		output ("</sub>");

		return 1;

	    case '^':

		output ("<sup>");

		c = next_char ();

		scan_expr ();

		output ("</sup>");

		return 1;

	    case '{':

		c = next_char ();

		for (;;)

		{

		    status = scan_expr ();

		    if (!status || c == '}')

			break; 

		}

		c = next_char ();

		return 1;

            case '\\':

		c = next_char ();

		scan_word (buf);

/*

		if (strcmp (buf, "alpha"))

		    fprintf (out, "<font face=\"symbol\">a</font>");

		else if (strcmp (buf, "beta"))

		    fprintf (out, "<font face=\"symbol\">b</font>");

		if (strcmp (buf, "gamma"))

		    fprintf (out, "<font face=\"symbol\">g</font>");

		else

*/

#define ds(name,str) \

		if (!strcmp (buf, name)) \

		{ \

		    sprintf (buf_out, "<font face=\"symbol\">%s</font>", str); \

		    output (buf_out); \

		} \

		else

#define da(name,str) \

		if (!strcmp (buf, name)) \

		{ \

		    output (str); \

		} \

		else

#define ign(name) \

		if (!strcmp (buf, name)); else



		ds ("alpha", "a")

		ds ("beta", "b")

		ds ("khi", "c")

		ds ("delta", "d")

		ds ("Delta", "D")

		ds ("epsilon", "e")

		ds ("phi", "f")

		ds ("Phi", "F")		

		ds ("gamma", "g")

		ds ("Gamma", "G")

		ds ("eta", "h")

		ds ("iota", "i")

		ds ("kappa", "k")

		ds ("lambda", "l")

		ds ("mu", "m")

		ds ("nu", "n")

		ds ("pi", "p")

		ds ("Pi", "P")

		ds ("theta", "q")

		ds ("Theta", "Q")

		ds ("rho", "r")

		ds ("sigma", "s")

		ds ("Sigma", "S")

		ds ("tau", "t")

		ds ("omega", "w")

		ds ("Omega", "W")

		ds ("xi", "x")

		ds ("psi", "y")

		ds ("Psi", "Y")

		ds ("zeta", "z")



		ds ("partial", "¶")

		ds ("int", "ò")

		ds ("sqrt", "Ö")

		ds ("Box", " ")

		ds ("nabla", "Ñ")    

		ds ("leftarrow", "¬")

		ds ("rightarrow", "®")

		ds ("infty", "¥")

		ds ("sum", "S")

		ds ("Sum", "S")



		da ("hat", "^")

		da ("\\", "<br>")

		/* da ("frac", "/") */



		da ("section", "<p>")

		da ("subsection", "<p>")

		da ("vskip", "<p>")

		da ("stackreldef", "[def]")



		ign ("begin")

		ign ("end")

		ign ("nonumber")

		ign ("displaystyle")

		ign ("limits")

		{	

		    sprintf (buf_out, "\\%s", buf);	

		    output (buf_out);

		}    

		return 1;



	    case '&':

		c = next_char ();

	    default:

		fputc (c, out);

		c = next_char ();

		return 1;

	}

    

}



scan_tex ()

{

int status;

    for (;;)

    {

	status = scan_expr ();

	if (!status)

	    break;

	if (c == '$' /* || c == '"' */ )

	    break;

    }

}



scan_html1 ()

{

char buf[1000];

char buf_out[1500];

char buf_com[2000];

int i, j;    

int status;

        switch (c)

	{

	    case '<':

		c = next_char ();

		if (c == '!')

		{

		    j = 0;

		    for (;;)

		    {

			buf_com[j++] = c;

			c = next_char ();

			if (c == '>' || c == EOF)

			    break;

		    }

		    /* buf_com[j++] = '$'; */

		    buf_com[j] = 0;

		    output ("<");

		    output (buf_com);

		    /* output (">"); */

		    return 1;

		}

		scan_word (buf);

		if (!strcmp (buf, "IMG") || !strcmp (buf, "img"))

		{

		    sprintf (buf_out, "<%s", buf);

		    for (;;)

		    {

			while (! ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z')))

			{

			    sprintf (buf_out+strlen(buf_out), "%c", c);

			    if (c == '>')

			    {

				output (buf_out);

				return 1;			    

			    }

			    c = next_char ();

			}

			scan_word (buf);

			strcat (buf_out, buf);

			if (!strcmp (buf, "ALT") || !strcmp (buf, "alt"))

			{

			    j = 0;

			    while (c != /*'$'*/'"' && c != EOF)

			    {

				c = next_char ();

				if (c == '"')

				    j++;

				if (j > 1)

				{

				    output (buf_out);

				    return 1;

				}

			    }

			    c = next_char ();

			    if (c == '$')

				c = next_char ();

			    else

			    {

				for (;;)

				{

				    if (c == '"')

					break;

				    c = next_char ();

				}

				ptr = buf_com;

			    }

			    scan_tex ();

			    if (c == EOF)

				return 0;

			    while (c != '>' && c != EOF)

				c = next_char ();

			    output ("<!--");

			    output (buf_out+1);

			    output ("-->");

			    c = next_char ();

			    return 1;

			}

			else

			    printf ("%s not rec\n", buf);

		    }    

		}

		else    

		{	

		    /*

                    if (c == '>')

			sprintf (buf_out, "<%s", buf);

		    else

		        sprintf (buf_out, "<%s%c", buf, c);	

		    */

                    sprintf (buf_out, "<%s", buf);

                    output (buf_out);

		}    

		break;		

	    default:

		fputc (c, out);

		c = next_char ();

		if (c == EOF)

		    return 0;

	}

}



scan_html ()

{

    for (;;)

    { 

	if (c == EOF)

	    return 0;

	scan_html1();

    }

}



main ()

{

char in_filename[200], out_filename[200];



    printf ("Input file ? ");

    gets (in_filename);

    in = fopen (in_filename, "r");

    if (in == NULL)

    {

	perror (in_filename);

	return;

    }



    printf ("Output file ? ");

    gets (out_filename);

    out = fopen (out_filename, "w");

    if (out == NULL)

    {

	perror (out_filename);

	return;

    }



/*

    for (;;)

    {

	c = next_char ();

	if (c == EOF)

	    break;

	printf ("%c", c);

    }

*/



    c = next_char ();

    /* scan_html (); */

    scan_tex ();



    close (in);

    close (out);

}