1.Classes and Objects
2.Constructors and Destructors
3.Inheritance
4.Polymorphism
5.Dynamic Binding
The concepts of OOP in C++ are the same as for OOP in any other programming language: abstraction, encapsulation, inheritance and polymorphism.
There is none. While you can access databases from C++, the two concepts are fundamentally different.
Yes we can compile a c program using c++ compiler. Because c++ evolved from the c. c++ have some additional features beyond c. c++ support almost all concepts used in c.
Learning C before C++ may be considered beneficial, as the concepts in C++ expound upon the concepts of C. However, it is unnecessary to learn C, as virtually any C++ course or resource will include all of the fundamentals that were inherited from C. Also, some concepts in C changed in C++ (to better methods), so learning C first will cause the learner to have to change some of their habits when they move to C++. For example, in C you would exclusively use printf for outputting to a screen, while in C++, you would want to use stream classes, so there would be some unnecessary learning.
Lambda expressions were introduced with C++11. They are not portable with earlier versions of the standard.
b+b+b+c+c+c+c =3b+4c
c + c + 2c + c + c = 6c
b + b + b + c + c + c + c = 3b + 4c
4c
c + c + c + c + c = 5 * c.
Computer Concepts & Programming
There are no "primary and secondary keys" in c and c plus plus.