Interview question asked in Pitney Bowls for C++ developer

Interview @ Pitney Bowls, Noida

1st Round:- Coding Round Online::
Three questions where asked. All need to be programmed with production level code.
It was in Hackerrank.com


2nd Round:Technical (SQL + Unix)
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*****Unix*********
How to check version of linux?
How to check shell of putty(ksh,?
How to check terminal of putty?
What is the meaning of writing #bash bla bla in first line of shell scrip? It is necessary?
awk,find,grep,sed, command?
In a file there is multiple columns. A column may have repeated data. How do you print unique elements of the nth column?
How to memory taken by a process while execution.
*******sql*******
How do you connect database in C++? Write the command?
Questions on join?
Given a problem o multiple tables and asked to write select query.
Importance of Indexes?
How a searching is performed in database, which algorithm is used?
While doing database search operation from multiple tables temporary table is created. How do you access that temporary table.
How do you optimize the sql query?
How to use show plan for sql?

3rd Round (C++,Data Structure)
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1. Asked about the questions in coding round. :: I was not able to recall even one problem.. :(
2. Gave one of the problem from coding round. (There is file containing n statements, two set of words for Apple company and another for Apple fruit. Now you have check each statement/line is concerned with Apple Company or Fruit and print either "Company" or "Fruit" for each line.)
3. What is Binary Search Tree?
4. In a binary tree there comes a situation that we can not add an item at some specific node due to left-right restriction. You need to find that kind node in binary tree.
Example:-
6
2 8
7 13
We can not add anything in the node 7. You need to find this kind of node in any binary tree.
4th Round (Design)
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1. Is there a way to print Binary tree in the sequence in which its elements are added in the tree.
2. There is three set of texts, set A,B and C. Each set is having size of 1024KB. There are some words that are repeated in the texts. You need to list down the repeated words from each set. If one asks for the result in the mod of processing the file then give only the list of previously performed text set(Not the output list of current processing set.)