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C++ Day 39

  C++ Day 39 STL Containers (Deep Understanding & Real Usage) Till now, you already know arrays, vectors, loops, and STL algorithms. Today, we go one step deeper and understand STL containers , which are the backbone of modern C++ programming. In real projects and competitive coding, choice of container matters a lot. 1. What are STL Containers? STL containers are data structures provided by C++ to store data efficiently. They handle: memory management resizing element access performance optimization You focus on logic , not memory handling. 2. Categories of STL Containers STL containers are mainly divided into: Sequence Containers Associative Containers Unordered Containers Container Adapters 3. Sequence Containers These store data in sequence . 3.1 Vector Most used container in C++. vector< int > v; Key Features: Dynamic size Contiguous memory Fast random access Slower insertion in middle Example: v. push_...
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C++ Day 22

  C++ Day 21: Encapsulation and Abstraction

On Day 21 the focus is Generally on two important Object-Oriented Programming (OOP) principles:


Encapsulation


Abstraction


These help in Constructing secure modular and clean code.


📚 Topics Covered:

🔹 1. encapsulation

encapsulation is the bundling of information and methods that run along that information inside amp one system (class) spell restrictive point approach to around Parts


➤ example:

cpp

copy

edit

#include 

using namespace std;


class bankaccount {

private:

    image balance;


public:

    bankaccount(double initialbalance) {

        correspondence = initialbalance;

    }


    null deposit(double amount) {

        if (amount > 0)

            correspondence += amount;

    }


    null withdraw(double amount) {

        if (amount > zero && number <= balance)

            correspondence -= amount;

    }


    image getbalance() {

        take balance;

    }

};

🔹 ii. Abstraction

Abstraction means hiding Complicated Applyation details and only exposing essential Characteristics.


Think of it like driving a car, you do  need to know how the engine works to drive.


➤ Example:

cpp

Copy

Edit

class Remote {

public:

    void powerOn() {

        cout << "Powering on the device.\n";

    }


    void changeChannel(int channel) {

        cout << "Changing to channel " << channel << endl;

    }


    // Internals like signal transmission are hidden

};

🔹 3. benefits

clean and standard code


easier to hold and debug


protects information from wildcat access


🛠️ do task

Make amp family employee with:


private members: list salary


public methods: setname() setsalary() getdetails()


Apply right encapsulation away preventing point approach to salary


📌 summary:

concept purpose

encapsulation protects information and keeps it good from abuse

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