I recently went through the PhonePe hiring process (OA + 3 rounds) and wanted to share my experience.

OA:
There were 4 questions, 2 from DP, 1 from Trees, and 1 was a bit different.
The last one was: given a number in the form of a string (length up to 47) and an integer B, we can pick digits from the string (in order) to form numbers. The task was to count how many numbers greater than B can be formed.
Out of the 4, I could fully solve 2 and partially solve the other 2. I still got shortlisted.

Round 1 (Technical):
Both questions were from LeetCode –

Burning Tree

Shortest Path to Get All Keys

I had to write the complete code on paper and also dry run it. The round lasted around 1 hour 10 minutes. I was able to answer both.

Round 2 (HM round):
This was more ad-hoc. I gave my best but the interviewer didn’t seem fully convinced. Luckily I still made it to the next round.

Round 3 (Technical):
Two problems again –

Codeforces 2028C

A custom problem: given a vector of pairs (a, b), you can pick any pair to start with. The next pair must satisfy a_next <= b_prev. The goal was to maximize the sum of all chosen b.

The constraints weren’t specified, so after discussing I suggested bitmask DP for small n (around 12–20). The interviewer asked me to proceed, and I wrote the solution on paper. Both problems were solved.

Feedback from both technical rounds was good, and by Shri Krishna’s grace I got shortlisted at the end.