Blogs

Intervals are a common topic in algorithmic problems. In this post, we’ll tackle five key interval problems: Insert Interval, Merge Intervals, Non Overlapping Intervals, Meeting Rooms, and Meeting Rooms II. Each problem will be solved with code examples and explanations. 1. Insert Interval Problem: Given a set of non-overlapping intervals sorted by their start time, insert a new interval into the intervals (merge if necessary) and return the result. Code Solution (Java):...

The Facade Design Pattern is a structural pattern that provides a simplified interface to a complex subsystem. It hides the complexity of the subsystem and makes it easier to use. The pattern involves creating a facade class that delegates requests to the appropriate components of the subsystem. Components of the Facade Design Pattern: Facade: The class that provides a simplified interface to the complex subsystem. Subsystem Classes: The classes that make up the complex subsystem....

The Decorator Design Pattern is a structural pattern that allows you to dynamically add behavior to an object without altering its structure. This pattern provides a flexible alternative to subclassing for extending functionality. Components of the Decorator Design Pattern: Component: The interface or abstract class defining the common interface for both the core object and decorators. ConcreteComponent: The class implementing the Component interface. This is the core object to which additional behaviors can be added....

The Composite Design Pattern is a structural pattern that allows you to compose objects into tree-like structures to represent part-whole hierarchies. This pattern treats both individual objects and compositions of objects uniformly. It’s useful when you need to work with hierarchies of objects and want to treat single objects and compositions of objects in a consistent way. Components of the Composite Design Pattern: Component: The abstract base class or interface that declares the common interface for both leaf and composite objects....

OAuth 2.0 is a widely used authorization framework that allows applications to access resources on behalf of a user without exposing their credentials. The diagram you provided visually represents the four primary OAuth 2.0 authorization flows: Authorization Code Flow, Implicit Flow, Resource Owner Password Credentials Flow, and Client Credentials Flow. Let’s explore each flow in detail to understand how they work and their respective use cases. 1. Authorization Code Flow Use Case: This flow is ideal for web and mobile applications where the client can securely store a client secret....

The Bridge Design Pattern is a structural pattern that separates an abstraction from its implementation, allowing the two to vary independently. This pattern is used to decouple an abstraction from its implementation so that the two can evolve separately without affecting each other. Components of the Bridge Design Pattern: Abstraction: Defines the abstract part of the interface that uses the implementation. RefinedAbstraction: Extends the Abstraction class and provides a specific implementation....

The Adapter Design Pattern is a structural pattern that allows objects with incompatible interfaces to work together. It acts as a bridge, converting the interface of a class into another interface that clients expect. This pattern is useful when you want to use an existing class but its interface doesn’t match the one you need. Components of the Adapter Design Pattern: Target: The interface that the client expects to use. Adapter: Converts the interface of the Adaptee into the Target interface....

The Visitor Design Pattern is a behavioral pattern that allows you to define new operations on objects without changing their classes. It involves separating algorithms from the objects on which they operate. This pattern is useful when you need to perform operations on a group of objects with different types without altering their classes. Components of the Visitor Design Pattern: Visitor Interface: Declares a visit method for each type of element that can be visited....

The Template Design Pattern is a behavioral pattern that defines the skeleton of an algorithm in a base class but allows subclasses to override specific steps of the algorithm without changing its structure. This pattern is useful when you have a common sequence of steps that are shared among multiple subclasses but may vary in certain details. Components of the Template Design Pattern: Abstract Class (Template): Defines the template method that outlines the algorithm’s structure and includes some default behavior....

The Observer Pattern is a behavioral design pattern used to define a one-to-many dependency between objects. When one object (the subject) changes its state, all dependent objects (observers) are notified and updated automatically. This pattern is commonly used in scenarios where changes in one part of an application need to be reflected in other parts without tightly coupling the components. Components of the Observer Pattern: Subject: The object that maintains a list of observers and notifies them of any changes....