WRITTEN TEST

• 1 coding question (generally PayTm restricts the use of Java language only)
• 10 MCQs based on DS & Algos
• 10 MCQs based on Java language and concepts
• 13 MCQs based on SQL

SKILLS REQUIRED

• Java is highly preferable
• Data structures & Algos
• SQL
• Computer Networks
• APIs
• Big Data technologies are a plus

Apart from the above skills, one needs to be good in numbers, decision-making problem solving, and interpretation.

INTERVIEW GUIDELINES 

Round 1: Technical Round

• Create SQL tables to show the relation between a user and passport number where a user can have multiple passport number entries due to cancellation or reissuing.
• Draw tables writing all fields required, mention keys and relationship between user table and passport table.
• DS Question on Rotten Orange problem and binary search code (can be found on gfg)
• Find the missing number and duplicate number from the given array.
• How well do you know Socket Programming? List the benefits and drawbacks of Sockets in Java.
• Explain the various layers in the OSI model in the context to computer networking.
• What do you understand about the concept of Virtual memory?
• Explain callback functions in JavaScript with the help of an example.
• Practice the following questions: https://www.geeksforgeeks.org/search-in-row-wise-and-column-wise-sorted-matrix/ https://www.geeksforgeeks.org/search-in-row-wise-and-column-wise-sorted-matrix/ https://www.geeksforgeeks.org/count-palindromic-subsequence-given-string/

Round 2: Technical Round

• DS question: find the minimum no. of platforms required to schedule the trains(arrival and departure time is given)
• Explain the internal working of HashMap in java
• Arrange the students on the basis of marks. (override comparator of sort() method)
• What are polymorphism, inheritance, encapsulation, and abstraction?
• How to achieve multiple inheritances?
• What is multithreading?
• Differences between SQL and NoSQL DB, CAP theorem, ACID properties
• Design database tables for an application e.g. – Splitwise
• Find the minimum height of the given Binary tree.
• Write a program to print all nodes which are at a distance ""k"" from target node
• Difference between runnable vs callable?
• Difference between HashMap vs Concurrent HashMap?
• How to use filter and stream on list in java?
• How can one differentiate between local variables and global variables?
• What are the benefits and drawbacks of using a star topology in a computer network?
• Practice the following questions: https://www.geeksforgeeks.org/reverse-tree-path/ https://www.geeksforgeeks.org/sort-string-according-order-defined-another-string/

Round 3: Managerial Round

• Tell me something about yourself.
• Why do you want to switch the company?
• What are the challenges do you face till now?
• Which project do you liked the most and why?
• Team Conflict questions.
• What are your strengths?
• Do you have any Location constraints?
• What are some of your advantages and disadvantages?
• What is your motivation for wanting to work at Paytm?
• Please furnish me with any Paytm-related information you have.
• What value do you bring to Paytm, and how do you envision yourself contributing to the world while you're there?
• Is it possible for you to relocate to another part of the country?
• Explain who you are and what you know about yourself.
• What was it about Paytm that intrigued you in the first place?

MPLOYEE.ME TIPS

• Always explain your answers considering time complexity and space complexity in paytm interviews