SDE - 1

3 sections. 20 min each. 

section 1: 20 aptitude questions and was really hard. Avg no of questions solved is 4. 

section 2: 20 (C++ & Java) oops related questions and other output questions too. (level was good. G-Facts) 

In C++: mainly Virtual functions, virtual destructor, copy constructor, initializer list, virtual inheritance questions, inner classes, etc.
In java: mainly inner classes, Base reference, and Child object concept, overriding questions, etc. 


section 3: Write running code for the following problem:
Find 2 nos in a sorted array whose DIFFERENCE is given no K

Started with a simple question and moved in depth.
What is a dangling reference?
Moved on to what happens when we access it?
How to handle it? I said we can use reference count or std::auto_ptr to avoid dangling references. He was happy with the auto_ptr smart pointer concept.
Then what happens when another auto_ptr assigns previously assigned auto_ptr (i.e when we use assignment operator in auto_ptr)? I said only one auto_ptr can hold an object, so the old auto_ptr will point to NULL.
Now, what happens when Old auto_ptr tries to access an object (i.e NULL). I said runtime exception and program may crash.
Name the type of exception. I said maybe segmentation fault.

What is Zombie process? Write code to create Zombie process.
What is Orphan process? Write code in C to create Orphan process too.
One query. Given a table having attributes stud_name, English, phy, chem., maths. Write a query to display the name of student in descending order of their aggregate marks.