First round was coding round.It consisted 3 sections.
1st section contained 14 logical reasoning questions in 14 minutes fairly easy.
2nd section had 16 advanced quantitative questions in 16 questions not so hard.
3rd section had 2 coding questions in 60 minutes. Everybody had different set of questions. Mine were:
1.You are given n buses and their start and end points of their routes.The routes were on a straight line. You need to replace 2 buses with a new bus if their routes overlap and the replaced bus will cover the routes of both bus. At the end there should be no overlap . Find the max distance travelled by a bus after replacement of overlapping buses.
Explanation: Routes of 1st and 2nd bus overlap so replace them with a new bus which will have route 1 to 4.
New routes are:
1 4 (4-1=3)
So Max distance travelled is 4.
Note: This question is similar to activity selection problem.
2.You are given a string consisting of only 0 and 1. You can replace at most k 0’s in the string with 1. Find no of ways to obtain maximum length of consecutive 1’s in the string.
Explanation :We can change at most 2 0’s to 1 and the maximum length of consecutive 1 we can get after replacement is 4 and strings with this property will be 11110010, 01111010 and 01011110 i.e. 3 strings (ways).
I solved it using sliding window algorithm.
Second round was technical round. The questions that were asked to me:
1.Implement Huffman coding algorithm.
2.You are given two Y-shaped linked list means they will share a common linked list after certain point. Find their first common node. I told him two approaches, one using hashing and other using recursion.
3.Find floor of square root of a integer.
Then he asked me about Database concepts like normalization, indexing. Have you worked on any NoSql database and how it is indexed.
Third round was project round.He asked me to explain my project.
Apart from project he asked me a puzzle and a simple array question.
Puzzle was, you are given N balls and out of them 1 is heavy. You can only weight by putting balls on both side. Find minimum no of operations to find the odd ball.
And the question was, you are given a array with random integers.You need to find a index in array such that a[i]=i.
Need to tell if there is better time complexity than linear to solve the problem.
Last round was HR round. He pointed out mistakes in my resume. Then he asked me about my one standout strength. Why you want to join airtel and why you will leave airtel.
I was selected for FTE.