Question

Suppose you have a linked list composed of Nodes:

public class Node {
public Node next;
public E data;
}
Write a recursive definition (not the code) for contains, in the style from lecture.

Answer 1

A recursive definition for a 'contains' method in a linked list involves checking if the current node is null or contains the data, and recursively calling 'contains' on the next node otherwise.

Step-by-step explanation:

When considering a recursive definition for the contains method for a linked list, you will want to think about the method in terms of two scenarios: the base case and the recursive step.

The base case will check if the current node (the one on which contains is called) is null (meaning the end of the list has been reached without finding the element) or if the current node's data equals the element you are searching for. If neither of these conditions are met, the recursive step will call the contains method on the next node in the list. This process will continue until the base case is satisfied.

A recursive definition for the contains method in the given linked list class would be as follows:

If the current node is null, return false.

If the data of the current node matches the target data, return true.

Otherwise, recursively call the contains method on the next node in the list.

This definition checks each node in the linked list, and if the data matches the target, it returns true. Otherwise, it continues to the next node until either a match is found or the end of the list is reached.