# <string>

**[<string>](https://en.cppreference.com/w/cpp/header/string)** provides `std::string` (mutable) and `std::string_view` (read-only, C++17). `std::string` is a dynamic array of characters with O(1) amortized append, O(1) random access, and utilities like `find()`, `substr()`, `replace()`.

Use `std::string` for owned text; use `std::string_view` for non-owning references (parameters, returns).

## Example

This example demonstrates string length queries, indexing, searching, and replacement operations.

```cpp
// compile: g++ -std=c++11 -o stringexample stringexample.cpp
// run: ./stringexample
// description: string operations

#include <string>
#include <iostream>

int main() {
    std::string s = "hello world";
    
    std::cout << "length: " << s.length() << "\n";
    std::cout << "at index 6: " << s[6] << "\n";
    
    size_t pos = s.find("world");
    std::cout << "found at: " << pos << "\n";
    
    s.replace(0, 5, "goodbye");
    std::cout << "after replace: " << s << "\n";
    
    return 0;
}
```