Question

What is the key difference between the poll() and remove() methods when working with data structures like queues or lists?

Option 1: poll() returns the element at the front of the data structure without removing it, while remove() removes and returns the element at the front.
Option 2: poll() removes and returns the element at the front of the data structure, while remove() only returns the element at the front.
Option 3: Both poll() and remove() perform the same operation of removing and returning the element at the front of the data structure.
Option 4: poll() and remove() are entirely unrelated methods and have no specific functionality in common.

Answer 1

The key difference is that poll() removes and returns the front element or returns null if empty, while remove() does the same but throws an exception if empty.

Step-by-step explanation:

The key difference between the poll() and remove() methods, when dealing with queues or lists in data structures, lies in their handling of elements. Option 1 is incorrect because poll() indeed removes and returns the element at the front. Option 2 declares remove() only returns the element at the front, which isn't true since remove() also removes the element. Option 3 is incorrect because there is a difference in their behavior when the data structure is empty. Option 4 is incorrect since poll() and remove() have common functionalities related to element removal.

The correct operation is that poll() removes and returns the element at the front of the data structure or returns null if the data structure is empty. On the other hand, remove() removes and returns the element at the front as well, but it throws an exception if the data structure is empty. This behavior makes poll() a better choice for queues because it's designed to handle cases where the queue might be empty without causing unwanted exceptions.