What is the basic functionality difference between a class and a structure?

Question

In C programming if i will declare a structure with private fields and some public methods, will it behave as a class?

Answer 1

A class's members are private by default, and a struct's are public:

class A {
    int x; // this is private to A
};

struct B {
    int y; // this is public
};

Also when it comes to inheritance, a class will inherit privately by default and a struct will inherit publically:

class C : B { }; // private inheritance

struct D : B { }; // public inheritance

That's it.