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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++ Day1

Theoretically part will begin day one of our C++ course. The fundamental concepts are:



Day 1: Basics of C++: What is C++?



A broad, compiled, high-performance programming language is C++. Essentially C with object-oriented features, it is a superset.



It was designed by Bjarne Stroustrup early in the 1980s.



It assists procedural, object-oriented, and generic programming.



Embedded firmware, driver creation, game development, system/software development, client-server applications, and embedded firmware are among C++'s most important uses.



Basics C++ Program Structure:



# include



int main() { // Starting point of the main function

std::cout < ;

Return 0;

}}





Explanations:



Add &lt;iostream; this covers the library for input and output.



int main() { . . . }; the primary function—every execution begins here.



std::cout displays output.



Return 0: The software ran without mistake.



Concerning the Basics:











Variable and Data Type



Variables house values.



Usual kinds include:



Integer; int



Floating decimal numbers: float



Single character: char



bool, Boolean (true/false)



double: Decimal with double accuracy.











Arrival and Exit



Variable: std::cin > > Input



std::cout &lt;&lt variable; output











Responses



Single-line comments are these:



multi-line:



This is

comment with multiple lines













Operators



Arithmetic: +, -, /, %



Comparison: ==, ! =, &gt;, &lt;, &gt;=, &lt;=



Logical: & amp;,

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