# Paytm Interview Experience for Software Engineer | 6 months Internship + FTE (On-Campus)

**Round 1**: This round was held on cocubes platform, In which 3 coding questions had to be solved in a time span of 70 minutes.

- Remove alternate characters of a given string starting from the left (3 marks)
- Odd number at odd index and even number at even index (3 marks)
- find all occurrence of the word in a matrix (5 marks)

I was able to solve the first two questions completely and the third one partially(except one test case). A total of 66 students out of 146 was selected for the second round.

**Round 2(75 mins)**: This was a technical interview round. The interviewer was friendly. He started by asking questions on data structure and algorithms.

- Knight tour problem in which initial and final positions was given, and I was asked to find the minimum number of moves to reach the final position. First, he asked me to explain the approach and then asked me to write pseudo code for this. I told him the most optimized solution, and he was satisfied with that.
- He asked me what is a binary heap, minimum heap, and maximum heap. Then asked me to write pseudo code for minimum heap implementation and also asked me the time complexities for its operations.
- Reverse a stack using recursion: I explained to him the approach, but I was not able to write the code completely, so the interviewer gave me some hints, and then I was able to solve it completely.
- He asked what is Topological sort and also asked me to write the topologically sorted array for some given graphs.

Around 32 students were selected for technical interview round 2.

**Round 3(45 mins)**: The interviewer was a Senior software engineer in the company. He was quite friendly. Firstly he asked me to introduce myself. Then he asked me which language and data structures I knew. After this, he started asking questions on DSA.

- Check if a string is substring or not: He told me to open the code editor and write the code.
- Implement Queue using stack: firstly I explained to him the approach then wrote the code for the same, and he was satisfied with it.

Then questions from MySQL, SQL, OS were asked, some of were:

- What is MySQL
- What are the stored procedures?
- Difference between WHERE and HAVING clause
- Layers of OS
- What is the Data layer?

After this, questions related to my projects were asked.

Finally, he asked me if I had any questions for him. I asked him about his journey in Paytm and the technologies that he is currently working on.

A total of 14 students were selected, and I was one of them.

I would really like to thank GFG for the best content, it helped me a lot in my preparation.