C++ Interview questions Part 13

C++ interview question:List out some of the object-oriented methodologies?
Answer: 

Ø Object Oriented Development (OOD) (Booch 1991,1994).
Ø Object Oriented Analysis and Design (OOA/D) (Coad and Yourdon 1991).
Ø Object Modelling Techniques (OMT) (Rumbaugh 1991).
Ø Object Oriented Software Engineering (Objectory) (Jacobson 1992).
Ø Object Oriented Analysis (OOA) (Shlaer and Mellor 1992). The Fusion Method (Coleman 1991)

C++ interview question: Name some pure object oriented languages?
Answer:
Ø Smalltalk,
Ø Java,
Ø Eiffel,
Ø Sather.

C++ interview question: What is an USECASE? Why it is needed? 

Answer:Use Case is a description of a set of sequence of actions that a system performs that yields an observable result of value to a particular action. In SSAD process <=> In OOAD USECASE. It is represented elliptically.

C++ interview question :Can we generate a C++ source code from the binary file?
Answer: Technically this is possible, but in my knowledge their no such software available yet. Why this is possible? In program flow we do like this to generate binary file. High level language programming code -low level programming code- hex code- binary code. How we can do reverse can be illustrated with this example. When I type 0 on screen the ASCII equivalent is 65 and so the binary code will be by converting 65 (01010 0101) so I can recognize this and decode this. Same technique can be used. Some secret mission defense org. I heard have this code splitter from binary to assembly language (low level language)/ Converter type devices available, they use them for secret national purpose.

C++ interview question : What is a memory leak? How can we avoid it? 

Answer :A memory leak can be avoided by making sure that whatever memory has been dynamically allocated will be cleared after the use of the same. for example

int main()
{ char *myCharData[20];
for (int nLoop =0;nLoop < 20; ++nLoop) { myCharData[nLoop ] = new char[256];
strcpy(myCharData[nLoop],"SABITH");
......
}
........................
/*Some manipulations here using myCharData*/
/*Now here we have to clear the data. The place can vary according to ur program. This being a simple program,u can clear at the end*/
for(int nLoop =0;nLoop < 20; ++nLoop)
{
delete[] myCharData[nLoop ];
}
return 0;

C++ interview question: What is virtual class and friend class? 

Answer: Friend classes are used when two or more classes are designed to work together and virtual base class aids in multiple inheritance

C++ interview question:Why does the function arguments are called as "signatures"?
Answer: The arguments distinguish functions with the same name (functional polymorphism). The name alone does not necessarily identify a unique function. However, the name and its arguments (signatures) will uniquely identify a function.In real life we see suppose, in class there are two guys with same name, but they can be easily identified by their signatures. The same concept is applied here.

ex: class person
{
public:
char getsex();
void setsex(char);
void setsex(int);
};
In the above example we see that there is a function setsex() with same name but with different signature.