Media.net (Directi) Senior Web Developer Interview Experience

One of my friends is working in Media.net, which was a part of Directi, as a Senior Web Developer. Read below his experience on the interview he had there:

Round 1: Shared Doc based Algorithms Round:

This was a Video Conference based interview where two interviewers connected over Google Hangout from Mumbai. I was asked to write the code in a shared Google Doc. I was asked to solve three questions:

• Reverse a string not considering the special characters.
• Write a program to calculate pow(x,n).
• Maximum difference between two elements such that larger element appears after the smaller number.

Round: 2: Pen Paper based F2F round:

After getting shortlisted, the HR informed me that they were willing to take further interviews in Bangalore. The focus was primarily on problem solving, SQL knowledge and JavaScript knowledge. I was asked following questions in this round:

• Given arrival and departure times of all trains that reach a railway station, the task is to find the minimum number of platforms required for the railway station so that no train waits. We are given two arrays which represent arrivals and departures of trains that stop.
• SQL Query containing 2 joins.
• Puzzle based on probability: You are about to get on a plane to Seattle. You want to know if you should bring an umbrella. You call 3 random friends who live there and ask each independently if it's raining. Each of your friends has a 2/3 chance of telling you the truth and a 1/3 chance of messing with you by lying. All 3 friends tell you that "Yes" it is raining. What is the probability that it's actually raining in Seattle?
• Given a matrix of n x n size, the task is to find the saddle point of the matrix. A saddle point is an element of the matrix such that it is the minimum element in its row and maximum in its column.
• Javascript question to implement prototype based inheritance.
• Write your own polyfill for Array.prorotype.map()

Round 3: Pen Paper based F2F round: 

This round happened on the same day. After clearing round 2, I was invited further for this round. The focus was on writing clean and executable code which manages all the test cases. Here are the questions asked in this round:

• Write a code to find the serial code of flight seat, from the given seat number. For example, if seat number is 12, serial code should be 2F. If seat number is 3, serial code will be 1C. It is as per flight seat arrangement in a normal domestic flight flying in India. 
• Extension to the above code: Find if seat is window seat or not.
• Extension to the above code: Find the nearest window seat code of given seat number.  For example if given seat number is 4, nearest window seat code is 1F.
• Write the internal implementation for JSON.stringify() in JavaScript.
• Project details worked on in the last organisation and testing frameworks used. 

Round 4: Video Conference based Managerial Interview:

In this round, a lot of focused was given on JavaScript fundamentals and Web based technology knowledge and understandings.

• All ES6 JavaScript fundamentals with inheritance, prototyping and new features.
• What is the importance of Cookies. What if we are not allowed to use cookies? How will you store the users data?

After a few days I got a call from the HR that they are willing to extend out an offer to me.