Languages / Beginner → intermediate

C and C++ guide

Core C/C++ syntax, memory, RAII, containers, references, pointers, and a path from procedural code to modern C++.

ccpppointersmemorystl

01Core language ideas

C gives direct control over memory and a small procedural model. C++ keeps that low-level power while adding classes, templates, RAII, the standard library, smart pointers, algorithms, and stronger abstractions.

Concept	Preferred modern C++ choice
Dynamic sequence	std::vector
Text	std::string
Ownership	stack value or std::unique_ptr
Shared ownership	std::shared_ptr only when truly shared
Iteration	range-for / standard algorithms

02Array-like storage

cppModern C++ vector

#include <iostream>
#include <vector>

int main() {
    std::vector<int> scores{91, 84, 88};
    scores.push_back(95);

    int total = 0;
    for (int score : scores) total += score;

    std::cout << "Average: "
              << static_cast<double>(total) / scores.size()
              << '
';
}

03Pointers, references, and ownership

A pointer stores an address and can be null. A reference is an alias to an existing object and is commonly used for function parameters. Raw pointers are still useful for non-owning access, but ownership should normally be expressed with values, containers, or smart pointers.

cppRAII ownership with unique_ptr

#include <memory>

struct Node {
    int value;
    std::unique_ptr<Node> next;
};

int main() {
    auto head = std::make_unique<Node>();
    head->value = 10;
    head->next = std::make_unique<Node>();
    head->next->value = 20;
}