1. Singleton class - can we call a copy constructor or an assignment operator 2. 10 boxes contain mini boxes weighing 20kg each. 1 box contains mini boxes weighing 19kg. Find this box. 3. Write your own string class. 4. Can a constructor throw an exception 5. Can a destructor throw an exception 6. How would you know if a core file belongs to your exe 7. Reverse a string without using while or for loop 8. How are callbacks invoked 9. What is the entry point for a shared object or a DLL 10. Find if a number(not a string) is a palindrome or not. 11. Write the abs function for integer 12. How negative numbers are represented in memory(2s compliment) 13. Find out if a tree is symmetric( mirror image with root node as the axis)