[C++] What are the differences between classes and structs?

Q: What are the differences between classes and structures in C++?

A:

• Classes have private members by default, whereas structures have public members by default:
  Code:

  ---

  class CFoo
{
  void f() {}
};

struct SFoo
{
  void f() {}
};

int main()
{
  Cfoo c;
  c.f(); // error: 'CFoo::f' : cannot access private member declared in class 'CFoo'

  SFoo s;
  s.f(); // OK

  return 0;
}

  ---

• Classes have private inheritance by default, whereas structures have public inheritance by default:
  Code:

  ---

  class CBase
{
public:
  void f() {}
};

struct SBase
{
public:
  void f() {}
};

class CFoo : CBase
{
};

struct SFoo : SBase
{
};

int main()
{
  CFoo c;
  c.f(); // error: 'CBase::f' not accessible because 'CFoo' uses 'private' to inherit from 'CBase'

  SFoo s;
  s.f(); // OK

  return 0;
}

  ---