Collections in JAVA

3. . ArrayList Operations:
Write Java code to perform the following operations on an ArrayList:
- Add an element to the ArrayList.
- Remove an element from a specific index.
- Check if an element exists in the ArrayList.
- Retrieve the size of the ArrayList.
- Iterate through the ArrayList and print its elements.

4. HashMap Basics:
Create a HashMap in Java and perform the following operations:
- Add key-value pairs to the HashMap.
- Retrieve the value associated with a specific key.
- Check if a key exists in the HashMap.
- Iterate through the HashMap and print its key-value pairs.
5. LinkedList Operations:
Implement a singly linked list in Java and write code for the following operations:
- Add a node to the beginning of the list.
- Add a node to the end of the list.
- Delete a node with a specific value.
- Search for a node with a specific value.
6. Stack Implementation:
Implement a basic stack using an ArrayList in Java. Write code to perform the
following stack operations:
- Push an element onto the stack.
- Pop an element from the stack.
- Check if the stack is empty.
- Peek at the top element of the stack without removing it.
7. Queue Implementation:
Implement a queue using a LinkedList in Java. Write code to perform the following
queue operations:
- Enqueue (add) an element to the queue.
- Dequeue (remove) an element from the queue.
- Check if the queue is empty.
- Retrieve the size of the queue.
8. Sorting ArrayList:
Write Java code to sort an ArrayList of integers in ascending order using the
`Collections.sort()` method.