The pollFirst() method of NavigableSet interface in Java is used to retrieves and removes the first (lowest) element, or returns null if this set is empty.
Where, E is the type of elements maintained by this Set container.
Parameters: This function does not accepts any parameter.
Return Value: It returns returns null if this set is empty.
Below programs illustrate the pollFirst() method in Java:
Program 1: NavigableSet with integer elements.
First lowest element removed is : 0
Program 2: NavigableSet with string elements.
First lowest element removed is : A
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