Algorithms and Problem Solving

Algorithms

• Definition: A set of instructions to solve a specific problem or perform a particular task
• Types:
  • Recursion: A function calls itself until a base case is reached
  • Dynamic Programming: Breaking down a problem into smaller subproblems and solving each only once
  • Greedy Algorithm: Making the locally optimal choice at each step, hoping to find a global optimum
  • Divide and Conquer: Breaking down a problem into smaller subproblems and solving each recursively
• Analysis:
  • Time Complexity: Measuring the execution time of an algorithm (e.g., O(n), O(n^2), O(log n))
  • Space Complexity: Measuring the memory usage of an algorithm (e.g., O(n), O(n^2), O(log n))

Data Structures

• Definition: A way to organize and store data in a computer
• Types:
  • Arrays: A collection of elements of the same data type stored in contiguous memory locations
  • Linked Lists: A collection of elements, each pointing to the next element
  • Stacks: A Last-In-First-Out (LIFO) data structure, where elements are added and removed from the top
  • Queues: A First-In-First-Out (FIFO) data structure, where elements are added to the end and removed from the front
  • Trees: A hierarchical data structure, where each node has a value and child nodes
  • Graphs: A non-hierarchical data structure, where each node has a value and edges to other nodes

Computer Networks

• Definition: A collection of interconnected devices that communicate with each other
• Types:
  • LAN (Local Area Network): A network that connects devices in a limited geographical area
  • WAN (Wide Area Network): A network that connects devices over a larger geographical area
  • MAN (Metropolitan Area Network): A network that connects devices in a metropolitan area
• Protocols:
  • TCP/IP (Transmission Control Protocol/Internet Protocol): A set of protocols that govern communication over the internet
  • HTTP (Hypertext Transfer Protocol): A protocol for transferring data over the internet
  • FTP (File Transfer Protocol): A protocol for transferring files over the internet

OOP (Object-Oriented Programming)

• Definition: A programming paradigm that organizes software design around objects and their interactions
• Key Concepts:
  • Classes: Blueprints for creating objects
  • Objects: Instances of classes, with their own attributes and methods
  • Inheritance: A child class inherits the attributes and methods of a parent class
  • Polymorphism: An object can take on multiple forms, depending on the context
  • Encapsulation: Hiding the implementation details of an object from the outside world
  • Abstraction: Focusing on essential features and hiding non-essential details

Algorithms

• An algorithm is a set of instructions to solve a specific problem or perform a particular task
• Algorithm types include:
  • Recursion: a function calls itself until a base case is reached
  • Dynamic Programming: breaking down a problem into smaller subproblems and solving each only once
  • Greedy Algorithm: making the locally optimal choice at each step, hoping to find a global optimum
  • Divide and Conquer: breaking down a problem into smaller subproblems and solving each recursively
• Algorithm analysis involves measuring:
  • Time Complexity: execution time (e.g., O(n), O(n^2), O(log n))
  • Space Complexity: memory usage (e.g., O(n), O(n^2), O(log n))

Data Structures

• A data structure is a way to organize and store data in a computer
• Data structure types include:
  • Arrays: a collection of elements of the same data type stored in contiguous memory locations
  • Linked Lists: a collection of elements, each pointing to the next element
  • Stacks: a Last-In-First-Out (LIFO) data structure, where elements are added and removed from the top
  • Queues: a First-In-First-Out (FIFO) data structure, where elements are added to the end and removed from the front
  • Trees: a hierarchical data structure, where each node has a value and child nodes
  • Graphs: a non-hierarchical data structure, where each node has a value and edges to other nodes

Computer Networks

• A computer network is a collection of interconnected devices that communicate with each other
• Network types include:
  • LAN (Local Area Network): connects devices in a limited geographical area
  • WAN (Wide Area Network): connects devices over a larger geographical area
  • MAN (Metropolitan Area Network): connects devices in a metropolitan area
• Key network protocols include:
  • TCP/IP (Transmission Control Protocol/Internet Protocol): governs communication over the internet
  • HTTP (Hypertext Transfer Protocol): for transferring data over the internet
  • FTP (File Transfer Protocol): for transferring files over the internet

OOP (Object-Oriented Programming)

• OOP is a programming paradigm that organizes software design around objects and their interactions
• Key OOP concepts include:
  • Classes: blueprints for creating objects
  • Objects: instances of classes, with their own attributes and methods
  • Inheritance: a child class inherits the attributes and methods of a parent class
  • Polymorphism: an object can take on multiple forms, depending on the context
  • Encapsulation: hiding the implementation details of an object from the outside world
  • Abstraction: focusing on essential features and hiding non-essential details