Answer: We can set a Max Priority Queue in Java using a custom comparator so that the head of the queue will return the largest element in the queue. Q #3) Does the Priority queue allow duplicates Java? Answer: Yes. Priority Queue allows duplicate values.

Can queue have duplicates?

The first and most important difference is one is Set and the other is Queue, which means one doesn't allow duplicate while the other is FIFO data structure without any restriction on duplication.

Does tree set allow duplicates?

Since the set doesnot support duplicate entries, you will get only unique elements left with TreeSet. The easiest way to find duplicate entries from the given array is, create TreeSet object and add array entries to the TreeSet.