Software Engineer

1. He asked me to write an SQL query, “Given a table with duplicate rows, remove duplicate rows from table”. I was not able to solve this question.
2. He asked me to write an SQL query, “Given employee table with manager id, find manger id who manages highest number of employee”. I was able to solve using ‘group by’ and ‘count’.
3. What is normalisation and clustered index vs non-clustered index?
4. Asked me to write a multi-threaded program, “Create two thread, perform some operation on shared variable, avoiding race condition”, similar to producer-consumer problem. I was able to write code, but it did not working, maximam time was taken by this problem. At the end interviewer said to leave it because time was over.

You are given the arrival and departure times of N trains at a railway station in a day. You need to find the minimum of platforms required for the railway station such that no train waits i.e No train should wait for the platform to be clear or free.

You are given a string 'str' of length 'N'.

Your task is to reverse the original string word by word.

There can be multiple spaces between two words and there can be leading or trailing spaces but in the output reversed string you need to put a single space between two words, and your reversed string should not contain leading or trailing spaces.

Example :

If the given input string is "Welcome to Coding Ninjas", then you should return "Ninjas Coding to Welcome" as the reversed string has only a single space between two words and there is no leading or trailing space.