[c++] Function for C++ struct

Usually we can define a variable for a C++ struct, as in

struct foo {
  int bar;
};

Can we also define functions for a struct? How would we use those functions?

Structs can have functions just like classes. The only difference is that they are public by default:

struct A {
    void f() {}
};

Additionally, structs can also have constructors and destructors.

struct A {
    A() : x(5) {}
    ~A() {}

    private: int x;
};