C++: Const vs Non-Const Methods

What is the difference between const and non-const methods in C++?

In C++, const methods are those that do not modify the object they belong to, while non-const methods can change the object's state.

Can you give me an example of a const method?

Sure! Here's an example:

class MyClass {
public:
    int getValue() const { return value; }
private:
    int value;
};

In this example, getValue is a const method.

What happens if I try to call a non-const method on a const object?

If you try to call a non-const method on a const object, you'll get a compilation error because non-const methods can modify the object.

Are there any performance differences between const and non-const methods?

Generally, const methods can be optimized better by the compiler, as they guarantee not to modify the object, potentially leading to better performance.