Rule 8) states that in the public round anybody can re-use anybody's code. This means that somebody who missed the private round submission deadline can still submit his code and have it count in the public round. This also means that anybody can take any of the codes posted in the public round and improve the code base to gain a better score. However, taking e.g. the best-scoring code, adding a stroke to then make second place will not count. You must improve the score in order to have it counted, plus only the best submission by any coder will count. Thus, nobody could take over multiple spots in the ranking.
Hope this clears it up.
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There are two types of vessels, submarines and targets.
