49. What are the different ways a method can be overloaded?
The different ways to overload a method are given as follows:
50. Differentiate between an abstract class and an interface.
51. What are queues and stacks?
Stacks refer to a list in which all items are accessed and processed on the Last-In-First-Out (LIFO) basis. In a stack, elements are inserted (push operation) and deleted (pop operation) from the same end called top.
52. Define an event.
Whenever an action takes place in a class, that class provides a notification to other classes or objects that are assigned to perform particular tasks. These notifications are called events. For example, when a button is clicked, the class generates an event called Click. An event can be declared with the help of the event keyword.
53. What are structures?
Structure is a heterogeneous collection of elements referenced by the same name. A structure is declared using the struct keyword. The following is an example that creates a structure to store an employee's information:
The preceding example defines a structure emp and the members of this structure specify the information of an employee.
54. When do you really need to create an abstract class?
We define abstract classes when we define a template that needs to be followed by all the derived classes.