#include <stdio.h>
#include <unistd.h>
#include <ctype.h>


main(int argc, char **argv)
{
	char            *decode , buf[1024], *end;
	unsigned char	out[17];
	int		i, file_no=0, byte;
	ssize_t		len, offset=0;
	char		file_name[1024];
	FILE		*file=stdout;

	while (len = read(0, buf+offset, sizeof(buf)-offset)) {

	    decode = buf;
	    end = buf + len ;
	    offset=0;

	    while (decode < end) {
		if (*decode == ' ') { decode++; continue ; } ;
		if (isspace(*decode)) { decode++; continue ; } ;
		if ((end - decode) == 1) {
		  buf[0] = *decode; 
	    	  offset=1;
		  break;
		}
		if (sscanf(decode, "%02x", &byte) < 1) { decode++; continue ; } ;
		fputc(byte, file);
		decode += 2;
	    }

	}
}