Data Structures and Algorithms in Java[1].pdf - Fulvio Frisone

Visualizing Game Entry Insertion
To visualize this insertion process, imagine that we store in array entries
remote controls representing references to the nonnull GameEntry objects,
listed left-to-right from the one with highest score to the one with the lowest.
Given the new game entry, e, we need to figure out where it belongs. We start this
search at the end of the entries array. If the last reference in this array is not
null and its score is bigger than e's score, then we can stop immediately. For, in
this case, e is not a high score—it doesn't belong in the entries array at all.
Otherwise, we know that e belongs in the array, and we also know that the last
thing in the entries array no longer belongs there. Next, we go to the second to
the last reference in the array. If this reference is null or it points to a
GameEntry object whose score is less thane's, this reference needs to be moved
one cell to the right in the entries array. Moreover, if we move this reference,
then we need to repeat this comparison with the next one, provided we haven't
reached the beginning of the entries array. We continue comparing and
shifting references to game entries until we either reach the beginning of the
entries array or we compare e's score with a game entry with a higher score. In
either case, we will have identified the place where e belongs. (See Figure 3.2.)
Figure 3.2: Preparing to add a new GameEntry
object to the entries array. In order to make room
for the new reference, we have to shift the references
to game entries with smaller scores than the new one
to the right by one cell.
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