Paypal Interview Questions

Round 1:

1. 7 Balls puzzle.  1 ball is odd among 7. Find odd ball in minimum weighing.
2. Write a function to check whether a number is prime or not. Give more than one solution.
3. What are your strengths?
4. Why do u want to leave your current company?

Round 2:

1. Explain about semaphore including what happens exactly at OS level.
2. Asked what is the toughest programming problem I have solved recently.
3. What are your strengths?
4. Why do u want to leave your current company?

Round 3:

1. Asked to give output of few C++ program.
2. Explain about virtual constructor and  virtual destructor.
Why can't we have virtual constructor?
3. Hourglass Puzzle: We have two hourglasses . One measure 7 min and another 11 mins.
Find out how to measure 9 mins using two hourglasses.

4. Write any sorting algorithm and explain.
5. Puzzle again  :-P
A grid is given. Arrange 1 to 8 in that grid in such a way that no two consecutive numbers should be placed besides each other parrallely or diagonally.


Round 4:
1. Write a function to check whether two strings are anagram of each other or not.
2. Write a function to check whether two strings are rotation of each other or not.
Solution:  http://ideone.com/OJ1oWY

3. Write a function to find all permutation of strings.
Solution:  http://ideone.com/GNkDMa

4. An array A[] and sum s is given. Find subset in array for which sum is equal to s.
  Ex: A[]={1, 3, 11, 4};
    sum =8;
 subset is {1, 3, 4}