cpp-modern-features

# C++ Modern Features

Master modern C++ features from C++11 through C++23, including lambdas, move
semantics, ranges, concepts, and compile-time evaluation. This skill enables
you to write efficient, expressive, and maintainable modern C++ code.

## C++11 Features

### Auto Type Deduction

The `auto` keyword enables automatic type inference, reducing verbosity and
improving maintainability:

```cpp
// Traditional
std::vector<int>::iterator it = vec.begin();
std::map<std::string, std::vector<int>>::const_iterator map_it = mymap.find("key");

// Modern C++11
auto it = vec.begin();
auto map_it = mymap.find("key");

// Auto with initialization
auto value = 42;              // int
auto pi = 3.14;              // double
auto name = std::string("Alice"); // std::string
auto lambda = [](int x) { return x * 2; }; // lambda type
```

### Range-Based For Loops

Simplified iteration over containers and arrays:

```cpp
std::vector<int> numbers = {1, 2, 3, 4, 5};

// Traditional loop
for (std::vector<int>::iterator it = numbers.begin(); it != numbers.end(); ++it) {
    std::cout << *it << " ";
}

// Range-based for (C++11)
for (int num : numbers) {
    std::cout << num << " ";
}

// With references to modify elements
for (int& num : numbers) {
    num *= 2;
}

// With const references for efficiency
for (const auto& str : string_vector) {
    process(str);
}
```

### Lambda Expressions

Anonymous functions with capture capabilities:

```cpp
// Basic lambda
auto add = [](int a, int b) { return a + b; };
int result = add(3, 4); // 7

// Lambda with captures
int multiplier = 10;
auto multiply = [multiplier](int x) { return x * multiplier; };

// Capture by reference
int counter = 0;
auto increment = [&counter]() { counter++; };

// Capture all by value
auto func1 = [=]() { return x + y + z; };

// Capture all by reference
auto func2 = [&]() { x++; y++; };

// Mixed captures
auto func3 = [&sum, multiplier](int x) { sum += x * multiplier; };

// Mutable lambda (can modify captured va