SDE-1 at Zomato

How it went

What they would tell you

How to prepare

Their background

Round by round

1. 1

   OA90 min

   1. Minimize Tree Height with K Cut & Attach-to-Root Operations Problem: You're given a rooted tree. In up to K operations, you can:

   • Cut any subtree from its parent.
   • Attach it directly under the root. Goal: Minimize the height of the final tree and return it.

   2. Tree Node Stones – Make Adjacent Difference Exactly 1 Problem: You're given a tree with n nodes. Each node already has a number of stones assigned (some may be zero). You can only add stones (not remove). Goal: Add the minimum total number of extra stones so that for every edge (u, v): |stones[u] - stones[v]| == 1

   3. Fill Array Zeros with Positive Integers to Satisfy Adjacent |diff| ≤ 1 Problem: Given an array arr of length n, with some elements as 0, fill those positions with positive integers from [1, M] such that: |arr[i] - arr[i+1]| ≤ 1 Count the number of valid full arrays.

   • Minimize Tree Height with K Cut & Attach-to-Root Operations
   • Tree Node Stones – Make Adjacent Difference Exactly 1
   • Fill Array Zeros with Positive Integers to Satisfy Adjacent |diff| ≤ 1
2. 2

   Technical Round-190 min

   Started off with intro of both of us, then he deep dived into my internship project details, asked about the whole pipeline of the project ,my specific role, and some cross CS-fundamentals based on the project for eg:what activation function did you use, what was your model accuracy, etc. Then he asked some CS fundamentals:

   • What is Postgres?

   • Why you didn't use MongoDB?

   • When shall i use Postgres?

   • Do postgres satisfy ACID properties ?

   • CAP theorem ?

   • Is CAP theorem applicable to SQL ? What happens when you type zomato.com in the web browser? Then he deep dived into one of my personal projects and asked some cross-questions regarding it. Then he asked 3- DSA Q's in google docs.

   • LC- Easy - Missing Number

   • LC-Medium - Minimum Size Subarray Sum

   • LC-Hard - The Skyline Problem Then he asked few Q's related to my hackathon participation. And then finally he asked if i had any Q's for him.

   • Missing Number
   • Minimum Size Subarray Sum
   • The Skyline Problem

What came up