DAY 2 - Data Structures and Algorithms

What is the main difference between an array and a linked list?

• Linked lists allow index-based access while arrays do not.

• Arrays consist of nodes linked by pointers while linked lists do not.

• Arrays can grow dynamically while linked lists have fixed sizes.

• The main difference is that arrays have fixed sizes and allow index-based access, while linked lists are dynamic and consist of nodes linked by pointers.

How do you access an element in an array?

• Call arrayName.access(index) to retrieve an element.

• Use arrayName[index] to access an element.

• Use arrayName.get(index) to access an element.

• Access elements with arrayName[index + 1].

What are the advantages of using a linked list over an array?

• Higher memory overhead for small data sets

• Slower access time for elements

• Advantages of using a linked list over an array include dynamic size, efficient insertions and deletions, and better memory management.

• Fixed size allocation

Explain how a stack operates and its main principles.

• A stack can only store integer values and not other data types.

• A stack operates on the Last In, First Out (LIFO) principle, supporting 'push' and 'pop' operations.

• A stack operates on the First In, Last Out (FILO) principle.

• A stack allows random access to elements at any position.

What is a queue and how does it differ from a stack?

• A queue allows random access; a stack does not.

• A queue is LIFO; a stack is FIFO.

• A queue is FIFO; a stack is LIFO.

• A queue is a type of array; a stack is a type of list.

Describe a real-world scenario where a stack would be useful.

• A list for storing user preferences.

• A web browser's back button functionality.

• A database for saving user profiles.

• A queue for managing print jobs.

What is the time complexity of inserting an element in a linked list?

• O(1) for insertion at known position, O(n) for insertion at arbitrary position.

• O(log n) for insertion at known position

• O(1) for arbitrary position

• O(n) for all insertions

How do you implement a queue using two stacks?

• Use a single stack for both enqueueing and dequeueing.

• Implement a queue using three stacks instead of two.

• Transfer elements directly between two queues without using stacks.

• Use two stacks: one for enqueueing and one for dequeueing. Transfer elements from the enqueue stack to the dequeue stack when needed.

What are the common operations performed on an array?

• Copy, paste, delete, merge

• Display, print, save, load

• Access, add, remove, iterate, sort, search.

• Transform, encrypt, decrypt, compress

Explain the concept of dynamic arrays and their benefits.

• Dynamic arrays have a fixed size and cannot change after creation.

• Dynamic arrays provide benefits such as flexible sizing, efficient memory usage, and ease of element management, making them suitable for applications where the number of elements is not known in advance.

• Dynamic arrays are slower than linked lists for element access.

• Dynamic arrays require more memory than static arrays.