# Traveloka Interview Experience for SDE3(On Campus)

**Online Technical Objective Round 1**: The round had 50 questions about C++ and its outputs. It was conducted on Hackerrank. The time limit allotted was 75 mins.

After the first round, about 50 students had qualified for the second round.

**Online Coding Round 2 – **There were 2 questions to be solved.

Question 1: **N **nodes where given. Any two nodes where connected with each other if the **GCD (node1, node2)** was greater than a given threshold value**(T).** The problem was to find if two nodes given were having any path between them for Q queries.Applying modified BFS after creating the adjacency matrix passed most test cases.

Question 2.**Modified Coin Change Problem**.

There were **N** coins which had to be converted into **M** coins. If you were at **X** coins, then you could go to **(X + Y)** by adding **Y** coins where **Y** is a **prime factor** of **X**. Adding a Y constituted a **single** **step**. The problem was to find the minimum number of steps required for the conversion.The problem could be solved by **Dynamic Programming.**

**8** Students were selected after the Coding Round for interview rounds.

**Interview Round 1 : ** The interview was also online on skype. The interview began with the regular introductions. Then I was asked about my preferred language and the projects I did in them. Then some coding questions were asked.

Problem 1: Find the maximum path sum in a binary tree. The path could start and end at any node in the tree. I discussed with him my approach and he was quiet interested in it. He told me to write a pseudocode for it. Later he found some mistake and told me to re-check. After sometime I gave him a O(n) approach. He was satisfied with it.

Problem 2: Find LCA in a Binary Tree. I was stuck in finding LCA in a BST instead of a binary tree. So first I gave him a O(height) solution of finding LCA in BST. But he was expecting a O(n) solution for binary tree. So I gave him another solution to find LCA using path traversal in O(n).

Problem 3: There are N commits to a repository. For a particular commit x, it is known that there was no error in the repo and after a commit Y there is some mistake in the repository. The problem was to find the commit that caused the error.

I wrote the Binary Search Algorithm for the problem with complexity O(log(n)). After dry Run, he was convinced that the solution will work for the problem.

The round lasted for **1 hour .**4 students were further selected for the next round.

**Interview Round 2: **This round began with the introduction too. The interviewer asked me for the Previous round’s questions and my approach to them. ** **

**Problem 1: **I was given a Queue data structure that supports standard operations like enqueue() and dequeue().I had to implement a Stack data structure using only instances of Queue and queue operations allowed on the instances.

Solution : https://www.geeksforgeeks.org/implement-stack-using-queue/

**Problem 2:** Implement LRU cache. I was implementing it using hashed map and linked list O(n). He was expecting O(1) for page replacement. Then I used Queue using doubly linked list in my approach.

Solution: **https://www.geeksforgeeks.org/lru-cache-implementation/**

He then asked me another Problem-Solving Question. Some Memory Management concepts, Project related questions and DBMS concepts were asked. He wanted to know the reasons of choosing a technology over some other in my projects.

After that he asked if I had any questions. I asked him some questions. He answered my each question with explanation.

This round lasted for about **1 hour 15 minutes.**The interviewers were interested in knowing my approach to the DS problems rather than the code.

The complete process spanned for two days. I got selected for SLI+FTE. 4 students were offered both in the end.

## Please

Loginto comment...