What is the purpose of encapsulation in C++?

In C++, encapsulation is a key feature of object-oriented programming that allows data and functions that operate on the data to be encapsulated in a class, achieving data hiding and protection. The main roles of encapsulation include:

1. Data hiding: Encapsulation can make the data of a class private, only allowing access and manipulation through the class’s public member functions, thus preventing external access and modification of data, enhancing data security.
2. Code reuse: Encapsulating data and related operations within a class can enhance the reusability of the code and reduce the workload of writing repetitive code.
3. Simplified interface: Encapsulating helps to hide the implementation details of a class, exposing only the necessary interface to the outside, reducing the complexity and understanding cost for users.
4. Achieve information hiding: Encapsulation tightly binds data and functions that operate on the data together, achieving information hiding and making the interface of the class clearer and easier to maintain.

In general, encapsulation enhances the security, maintainability, and reusability of code, making it an important feature of object-oriented programming.