Assume the nodes a$,$ b$,$ c$,$ and $d$ have been declared and initialized so that they are connected as depicted in the image above.

Now, assume the following three statements execute:

$b.$next $=d.$next;

$d.$next $=a.$next;

$a.$next $=c.$next;

a$)$ After the above statements execute, what are the outputs of the following print statements?