**Round 1: Coding**

Q.1 A 5*5 matrix of spiral order is

Now for an N*N spiral matrix filled similar to one given above, find element present at [R,C] position where R=row’s number, C=column’s number.

Constraint: You can’t create matrix itself. Print number without creating matrix explicitly.

Q2. Given a string S and two indexes i & j, modify the string in a pattern such that:

characters from [0 to i] index are now at back of the string.

characters from [j till end of string] are in front of string.

e.g. S = “abcdef” and i=1, j=3.

Output should be: “defcab”

Constraint: Constant Space.

Q3. https://leetcode.com/problems/simplify-path/

**Round 2: Group Flyer**

Q1. Given an array of positive integers, sort the array in a manner such that when all the elements of new array are concatenated in a string, the number formed is maximum.

e.g. input: [12,9,32]

output: [32,9,12]

Q2. In a native language alphabets are in this order:

a b d c k l g h ng q r

given two string str1 and str2, find which one is larger among the 2. (larger means rankwise more e.g. if “da” and “c” are given then “da” > “c” as d comes first).

write this function:

bool compare(char* str1, char* str2); return 1, if str1 > str2. return -1, if str2 > str1 return 0, otherwise

Interviews: We needed to write our code on a paper.

**First F2F round: **

Q. https://leetcode.com/problems/letter-combinations-of-a-phone-number/

I did it using recursion and then he asked me to think about iterative approach. One que of DBMS, I told him I am from ECE and haven’t studied DBMS. Then he asked what courses I have done from CSE dept. I told him OOP, DS, Architecture, Network.

Finally he asked if I have any questions. I asked about diff b/w MSIDC and MSIT.

Second F2F Round:

Q1. http://www.geeksforgeeks.org/find-longest-path-directed-acyclic-graph/

He gave me this que and asked to solve it in 45 minutes. First he asked about approach. I told him the approach and procedure how I am going to code it.

Then he changed the question I don’t know why and next ques was:

Q2. In a degree ‘N’ tree. Find LCA of 2 given nodes. All elements are unique in tree.

First I gave him a general solution. He didn’t seem convinced because of space complexity and told me to think more. I answered approach in which we can store path from root node to given nodes and match the path. He was convinced then and told me to wait for 5 minutes before 3rd round.

**3rd F2F Round:**

He asked me about myself. Then he asked what part I like most in DS. I said trees, linked list.

Q1. Given 2 numbers ‘N’ and ‘M’ where ‘N’ > ‘M’ and last a range of indexs [i,j] between (1,32) which denotes indexes in binary representation of ‘N’, change all the bits in this range to bits of number ‘M’. Also (j-i) is equal to most significant bit of ‘M’

e.g. N=9 :: (binary) 000000…0001001

and M=2 :: (binary) 000000…0000010

and (i=1,j=2) implies 1 to 2 bits of N has to be changed such that they are equal to M’s bits.

expected output: 10 :: (binary) 000000…0001010

where (…) = 19 zeros

First I didn’t get it but then he explained with above example.

Answered it in O(32) in second go.

Q2. Populate next pointer in a binary tree in O(1) space.

http://www.geeksforgeeks.org/connect-nodes-at-same-level-with-o1-extra-space/

Q3. Something about Deadlock. I asked about the subject and He said OS. I told him I haven’t studied this. He calmly said “Ohh Okay no problem” 😛

Finally someone from their team told me “We are done for the day, You can leave” 😛

Total 11 students were selected.

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