Computer Science & Engineering
( Example FAQ in interviews)

C, Data structures, C++ & OOPS:

9) Given inorder & preorder traversal or inorder & postorder traversal of a tree, build a tree.

10) Why prototypes are used?
11) What are inline functions and scope resolution
12) What are pre-processors? What is their use?
13) Which is efficient sorting algorithm? Why? 1) What is dequeue, priority queue, Dangling pointer etc.
2) Differentiate between Calloc & Malloc, structures & unions, *p++ & ++*p etc
3) What are: Polymorphism

virtual functions, encapsulation, data hiding etc
4) Do virtual constructors & destructors exist?

5) What is the memory used by an integer pointer, float pointer  etc.        6) What are: binary tree, strictly binary tree, completely binary tree, almost complete binary tree, threaded binary tree, etc.  7) Conversion of expression from infix to postfix & to prefix

8) Evaluation of postfix and prefix expressions

||Note||: In most of the cases small program code is given & output is asked or to identify the error in it.

Operating Systems:

1) What is virtual memory? Differentiate between logical & physical memory
2) What are: demand paging, pure demand paging, page fault, page replacement, page replacement algorithms (LRU, Opt. FCFS etc), thrashing, paging, segmentation, external & internal fragmentation etc
3) Which technique does DOS (& UNIX) use? (Paging or Segmentation or both….)
4) What are scheduling algorithms? (FCFS, SJF, RR,…) [IBM]
5) Why you prefer SJF? Does it have any limitation?(ans: Starvation of longer processes) How do you over come it?( one solution is: by using priority queue with SJF)
6) What are semaphores and monitors?
7) What is critical section problem?
8) What is a process, BCP (Program Control Block)?
9) What is turnaround time, Throughput [IBM]?
10) What do you optimize using scheduling algorithms SJF, RR etc?
11) What is real time operating system, time sharing system, batch processing multiprogramming?

12) Differentiate Between multitasking and time-sharing system?
13) What is dead lock? Necessary condition
14) File accessing technique (direct, sequential)
15) File allocating techniques (contiguous, linked, indexed)
16) Free space management (rarely asked)
17) Head movement algorithms (FCFS, SHORTEST DISTANCE FIRST, SCAN,

Note: These questions on OS are asked only if you tell OS as your favourite subject.

1) What is normalization? Why is it needed?
2) What are insertion, deletion, & modification anomalies?
3) What is first, second, or third normal forms?
4) Do you implement it in your project, how explain with example?
5) What is super key, a key, candidate key, primary key or minimal super key etc?
6) What is entity integrity, referential integrity etc?

SYETEM SOFTWARE: (rarely asked)
1) What is an interpreter, differentiate between compiler and interpreter? (MIND TREE)
2) What are assembler, linker, loader, and dynamic linker?
3) What are Yacc, Parsing techniques, LR, LL, LALR grammars?

UNIX: (rarely asked)
1) Expand UNIX, who developed it, when & where?
2) What is file structure used in UNIX? [IBM]
3) Differentiate between UNIX & LINUX?
Some commands may be asked.

JAVA & NETWORKING: (Rarely asked)
1) What is the significant feature of JAVA? (ANS: JVM JAVA virtual machine)
2) Difference between package, interface, classes etc?
3) Difference between interfaces & abstract classes?
4) What is class A, class B, class C, class D addresses? (CIP)
5) OSI & TCP (IP layer and their function may be asked)
6) What is routing?
7) Difference between routes, bridges, & gateways?
8) What is firewall?
9) Difference between UDP & TCP?
10) What is subnet?

Note: question on SS, UNIX, JAVA, NETWORKS, OOPS, C++ are asked only in the pure software companies or big MNC’s or dream companies or if you say it as your favourite subject.

So don’t panic, be cool and feel confident. Yes, here a bit of luck is counted.
Speak clearly and convince your answers to them. Don’t rush at your answers and end up stammering, getting confused. Speak slowly and steadily; such are the guys who impress more. Smile in between (if you don’t know the answer) and don’t make too many hand movements. Don’t use complex terminology, which you don’t know. (Practicing mock interviews really helps a lot).
The technical interview may last for 15 to 45 minutes. With good preparation many people find technical interview easy.
If you do technical badly, then there is 90% chance of your rejection, if it was average, then one can do well in HR and get selected.