Solve problems that are commonly asked in C++ coding interviews related to common data structures.

Ace the C++ Coding Interview

Data structures are among the fundamentals of computer science and are often a core decision in developing efficient programs. They are categorized as a vital benchmark of computer science knowledge when it comes to industry interviews. This module contains a detailed review of common data structures in C++. We'll also become well-equipped with different data structures by implementing them.
By the end of this module, we'll have expertise in solving problems in data structures.

Data Structures



# Which is Better?

**DLLs** have a few advantages over **SLLs**, but these perks do not come without a cost:

- Doubly linked lists can be traversed in both directions, which makes them more compatible with complex algorithms.
- Nodes in doubly linked lists require extra memory to store the `previousElement` pointer.
- Deletion is more efficient in doubly linked lists as we do not need to keep track of the previous node. We already have a backward pointer for it.

At this point, we've compared the two major types of linked lists. The minor memory load that comes with DLLs can be forgone because of the convenience they provide.

This doesn't mean that DLLs are perfect. There is always room for improvement!

Let's discuss a tweak which can improve the functionality of both types.

## Tail Pointer in a Linked List

The `head` node is essential for any linked list, but what if we also kept account of the **tail** of the list? Now, you are aware of both ends of a linked list. 



To add the `tail` functionality, all we have to do is add another member to our `LinkedList` class:


Let's see how the two renditions of the linked list structure fare against each other.

Singly Linked Lists vs. Doubly Linked Lists

Which is Better?