Shall this be a ringbuffer - like the clock, where it starts from the beginning after reaching the end: '..., 10, 11, 12, 1, 2, ...'?
Yes that's right, the next reference of the list's last node references the first node, instead of null.
Is the size of this circular list known in advance, or shall it be possible to in- and decrease it's size?
Now, I'm talking about index, so you might be thinking ... array? If your circular list is of fixed size, an arry would be a fine implementation.
since the question does not mention whether they want it to be fixed or expandable, so to make it a good program lets implement it as a reference-base list (expandable) . any suggestions?