Given the c code below what is printed to the after invoking the program what is printed to standard output,what is in fileB.txt$,$ and what is in fileA.txt$.$ All syscalls succeed

The program is invoked like the following:

$ cat fileA.txt

File text a

$ cat fileB.txt

File text b

$$./$a$.$out

$ echo $$hello world$$

Program:

char space$[100]$;

int B $=$ open$("$fileB$.$txt$",$ O$\_$WRONLY $|$ O$\_$CREAT $|$ O$\_$APPEND, $0666)$

int A $=$ open$("$fileA$.$txt$",$ O$\_$RDONLY$)$;

printf$("$Hi$!$

$")$;

dup$2($B$,$ STDOUT$\_$FILENO$)$;

printf$("$Good$?$

$")$

dup$2($A$,$ STDIN$\_$FILENO$)$;

for $($;;$)\{$

ssize$\_$t b$\_$read $=$ read$($STDIN$\_$FILENO, space, sizeof$($space$))$; if $($b$\_$read $==0)$

return $0$;

ssize$\_$t b$\_$write $=$ b$\_$read; while $($b$\_$write $>0)$

b$\_$write $-=$ write$($STDOUT$\_$FILENO,

space $+$ b$\_$read$-$b$\_$write, b$\_$write$)$;

$\}$