HCL HR approached me for an interview for a contractor role at Cisco.

The first round was a telephone interview with an HCL Manager.

After clearing that, I had a telephone interview with a Cisco Manager.

This was followed by two in-person technical interviews at the Cisco office.

This is a list of some questions I was asked during the interview process.

Telephone Interview Questions

1. Volatile: Explain the volatile keyword with a scenario where it would be used. Discuss other scope variables.

Inheritance

1. Constructor, copy-constructor
2. Multiple constructors and destructors
3. Difference between a copy-constructor and an overloaded assignment operator
4. Write a program to reverse a string without using in-built functions.
5. Assigning a value to a constant pointer
6. Difference between a char pointer and a char array
7. Will the size of a char pointer and a char array be the same?
8. Allocating memory for a 2D array using malloc.
9. More emphasis on pointers.
10. OOPS concepts, for example, inheritance (multiple vs. multi-level inheritance).
11. Difference between a copy-constructor and an overloaded assignment operator.
12. What is STL?
13. Exception and error handling.
14. Runtime polymorphism with an example.
15. Problems with multi-threaded programming and how to overcome them.
16. Given a scenario, how would you come up with a class design?
17. Explain any design pattern you are aware of with examples (other than the singleton pattern).
18. Difference between a thread and a process.
19. How can inter-process communication happen?
20. How to debug a program? How to debug a crash?

Face to Face Discussion

Round 1:

1. Static and Dynamic Libraries:

   • Difference between them.
   • Why do we need static libraries and not just use dynamic ones?
   • Does the binary size (.exe file) change depending on the type of library used?
   • Will the libraries still be required even after the binary is generated?

2. Why does a program compiled on a Windows system (exe) not run on Linux/Mac?

3. Explain the steps that happen when you enter a URL in a browser until the webpage is displayed.

4. What is a VPN? What purpose does it serve?

5. Why do we need to use a proxy server? What are its uses?

6. Program: Find the maximum occurrences of a number in an input sequence.

   • Example: If the input sequence is 1, 2, 2, 3, 4, 4, 3, 4, the answer is 3 (4 is repeated 3 times).
   • Same program, but the input sequence can be very large, and each number can range from 1 to a million. How would you calculate this?

7. Questions about processes, threads, and IPC.

Round 2:

1. Consider two sorted arrays A[50] and B[20]. Array A has 30 elements arranged in the first 30 spaces, and array B is filled with 20 elements. Now, merge the elements of B with A in sorted order with O(n) time complexity.

2. Consider two sorted arrays A[120] and B[100]. Both arrays are filled with elements. Find the middle-most element (the 110th element if both arrays were merged in sorted order) without actually creating a new array and merging the two arrays.

3. Can realloc be used to free memory?

4. What is the "this" operator? What happens when delete this is called in the destructor of a class?

5. In a knockout tournament with 64 teams, where two teams compete at a time, how many matches will the winner have to play?

6. In an IPL match with 8 teams, how many matches will the winner have to play?