Databorough Software Developer Interview Questions and Answers

Q1. I am freshers soo please one chance for your company
Add your answer
Q2. Yes I am fresher soo for your company work
Add your answer
Q3. Talk about a range of elements, including customer service.
Ans. 
Customer service is an essential element in software development.
• Customer service involves providing support and assistance to users of software applications.

• It includes addressing user queries, resolving issues, and ensuring customer satisfaction.

• Software developers may interact with customers through various channels like email, phone, or live chat.

• Good customer service can lead to positive user experiences and incre...read more
Answered by AI
Add your answer

Q1. Burn A Node in a Binary Tree
Ans. 
To burn a node in a binary tree, we mark the node as burned and then recursively burn its left and right children.
• Mark the current node as burned

• Recursively burn the left child

• Recursively burn the right child
Answered by AI
Add your answer
Q2. In depth questions on current projects
Add your answer

Q1. Disjoint Set Question
Add your answer

4 interview question

Q1. Task schedular from leetcode second is : N piles of coins diffrent length you can add or remove one coin from a pile adding cost c1 and removing cost c2 find minimum cost such that height of n piles equal...read more
Ans. 
Find minimum cost to make heights of N piles of coins equal by adding or removing one coin from a pile with different costs.
• Use dynamic programming to keep track of the minimum cost for each pile height.

• Consider the cost of adding and removing coins from each pile.

• Iterate through all possible combinations of adding and removing coins to find the minimum cost.
Answered by AI
Add your answer
Q2. Question on polymorphism overloading overriding
Add your answer
Q3. C++ fundamentals
Add your answer

Round duration - 120 Minutes
Round difficulty - Hard

Online Test Platform - HackerRank
Test Access Window – between 10:00 AM to 6:00 PM
Online Test Pattern –

Total Duration of Test – 120 mins
Total No. of Sections - 5
Section 1 – One Coding Question - Easy difficulty (20 mins)
Section 2 – One Coding Question - Medium difficulty (30 mins)
Section 3 – One Coding Question - Medium difficulty (30 mins)
Section 4 - Technical MCQs - 10 questions (20 mins)
Section 5 - Aptitude MCQs - 10 questions (20 mins)
Programming Sections (1, 2 and 3): This will have 3 coding questions with a time limit of 80 minutes. It is mandatory for you to attempt the 1st coding question before moving to the second question and third. You cannot revisit question/section once you proceed ahead
MCQ Sections (4 and 5): This will have 10 technical and 10 aptitude questions, with a time limit of 20 minutes each. Each correct answer will carry 2 marks and wrong answer will carry negative 0.5
Technical questions will cover Data structures & algorithms, Operating systems, Database systems, SQL and Networks.
Aptitude questions will cover Quantitative Aptitude, Problem solving and Logical & verbal Reasoning

Q1. 
Tower Building Problem Statement
Given an array 'ARR' of 'N' cubes, you need to construct towers such that each cube can either be placed on top of an existing tower or start a new one. The restriction is...read more
Ans. 
I stored the difference in heights.
Sorted this array
And filled the difference such that max length is observed.
Answered Anonymously
Add your answer
Q2. 
Minimum Removals Problem Statement
Given an array ARR of size N and an integer K, determine the minimum number of elements that must be removed from the array so that the difference between the maximum an...read more
Ans. Brute Force
We will first sort the given array. Then we will start traversing the array using two variables, say ‘i’ and ‘j,’ using a nested loop, where j will be used to fix the maximum element, and i will be used to fix the minimum element and check if arr[j] - arr[i] <= K.
 
Algorithm:
 
1. Sort the given array in increasing order.
2. Make an integer variable “answer” = N to store the minimum number of elements tha...read more
Answered Anonymously
Add your answer
Q3. 
Conquering the Best Kingdom Problem Statement
Aragorn, an influential ruler, aspires to expand his power by conquering more kingdoms. There are 'N' kingdoms numbered from 0 to N-1, forming a tree structur...read more
Ans. Greedy + Depth First Search
The question becomes easy if you are able to figure out that only the decision of selecting the first kingdom to conquer will be sufficient to determine the final answer. Let’s start with something more intuitive rather than directly jumping to the final answer. If you pick a random kingdom in your first turn, in subsequent turns both you and Aragorn you will greedily conquer all the kingdoms...read more
Answered Anonymously
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

They called and asked me to choose a date and time I would be free in the upcoming week for my interview.
I chose 10th March 5 pm. 

Interviewer was pretty friendly. Started with some resume based questions. Asked me OS, DBMS and JAVA based questions. A coding question was asked to code. Asked me OOPS related questions too.

Q1. 
K Most Frequent Elements Problem Statement
Given an integer array ARR and an integer K, identify the K most frequent elements within ARR. Return these elements sorted in ascending order.
Example:
Input:
...read more
Ans. QuickSelect
Prerequisite: Quick Sort
 
In this approach, we will try to divide the problem at every step into a smaller problem. We know that the kth top frequent element is (n - k)th less frequent. So, we will do a partial sort from the less frequent element to the most frequent one, till (n - k)th less frequent element takes place (n - k) in a sorted array. To do so, we will use quickselect. Quickselect is an algor...read more
Answered Anonymously
Add your answer

Round duration - 90 Minutes
Round difficulty - Medium

This round had 3 coding questions. The first two were of moderate level and the third one was a bit hard and was related to Dynamic Programming.

Q1. 
Maximum Number from Linked List Problem Statement
Given a linked list where each node contains a single digit, your task is to construct the largest possible number using these digits.
Objective:
Print ...read more
Ans. 
Approach : 

1) Traverse the linked list from start to end and make frequency array of all digits (0-9) present in the linked list.

2) Make the string starting from the maximum of digits (0-9) present in the linked list i.e first append all the 9’s in the answer string then append all the 8’s at the end of the answer string so on for all the other digits in the decreasing order. 

3) Finally, return the formed ans...read more
Answered Anonymously
Add your answer
Q2. 
Chocolate Distribution Problem
You are given an array/list CHOCOLATES of size 'N', where each element represents the number of chocolates in a packet. Your task is to distribute these chocolates among 'M'...read more
Ans. 
Approach : 

1) Suppose the given array is ‘CHOCOLATES’.

2) Sort the given array.

3) Find the subarray with the minimum difference of the last and first elements.

4) To store minimum difference we use a variable (say, ‘minVal’) and the initial value is ‘INFINITE’

5) Run a loop from 0 to ‘N’ - ‘M’ - 1(say, iterator ‘i’)

6) If 'CHOCOLATES'[i] - ‘CHOCOLATES’[i - M + 1] is less than ‘minVal’ then update ‘minVal’ with ‘CHOCOL...read more
Answered Anonymously
Add your answer
Q3. 
LCS of Three Strings Problem Statement
Given three strings A, B, and C, determine the length of the longest common subsequence present in all three strings.
Explanation:
A subsequence is derived by dele...read more
Ans. 
Approach : 

1) The idea is to create a 3-D DP of size n*m*k.

2) Initially, all the elements of the DP table will be 0.

3) Now, the value DP[i][j] means denotes the length of the longest common sub-sequence of string A[0..i], B[0..j], and C[0..k].

4) The detailed algorithm to fill the DP table will be as follows:

Loop 1: For i = 1 to N:
Loop 2: For j = 1 to M:
Loop 3: For k = 1 to K:

if(A[i] == B[j] == C[k] ), DP[i][j][k] ...read more
Answered Anonymously
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

This round had 2 questions of DS/Algo to solve under 60 minutes and 2 questions related to Operating Systems.

Q1. 
Buy and Sell Stock Problem Statement
Imagine you are Harshad Mehta's friend, and you have been given the stock prices of a particular company for the next 'N' days. You can perform up to two buy-and-sell ...read more
Ans. 
Approach : 

1) Initialize variables 'FIRSTBUY' as the minimum negative value, ‘FIRSTSELL’ as 0, ‘SECONDBUY’ as the minimum negative value, and ‘SECONDSELL’ as 0.
‘FIRSTSELL’ will be the profit after the first transaction and ‘SECONDSELL’ will be the profit after the second transaction.

2) For ‘i’ in range days:
2.1) Maximise 'FIRSTBUY' as max( 'FIRSTBUY' , - ‘PRICES[i]’), this is the amount left after your first buy.
2...read more
Answered Anonymously
Add your answer
Q2. 
Count Smaller People on Right
You are provided with an array called HEIGHT that contains the heights of 'N' people standing in a queue. For each person in the array, compute the number of individuals on t...read more
Ans. 
Approach : This question was similar to the famous problem "Count Inversions" and so I thought of applying Merge Sort here. 

1) By modifying the merging array part of merge sort, we can calculate the required ans.

2) During merging of two halves, when the higher index element is less than the lower index element, it represents that the higher index element is smaller than all the elements after that lower index beca...read more
Answered Anonymously
Add your answer
Q3. Can you define processes and threads in operating systems?
Ans. 
Process : A process is an instance of a program that is being executed. When we run a program, it does not execute
directly. It takes some time to follow all the steps required to execute the program, and following these execution
steps is known as a process.

A process can create other processes to perform multiple tasks at a time; the created processes are known as clone
or child process, and the main process is known as ...read more
Answered Anonymously
Add your answer
Q4. What are the different types of semaphores?
Ans. 
There are two main types of semaphores i.e. counting semaphores and binary semaphores.

1) Counting Semaphores :
These are integer value semaphores and have an unrestricted value domain. These semaphores are used to
coordinate the resource access, where the semaphore count is the number of available resources. If the resources
are added, semaphore count automatically incremented and if the resources are removed, the count i...read more
Answered Anonymously
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

This round had 3 coding questions in which I first had to explain my approach with proper complexity analysis and then code up the solution. I found the first problem to be a bit on the harder side compared to the rest of the 2 problems.

Q1. 
Longest Increasing Path in a 2D Matrix Problem Statement
Given a matrix of non-negative integers of size 'N x M', where 'N' and 'M' denote the number of rows and columns respectively, find the length of t...read more
Ans. 
Approach : 

1) We maintain a 2D array dp of size N*M. Since the increasing path can start from any point in the matrix, we use dp[i][j] to store the length of the longest increasing path starting from location (i, j). This ensures that we do not recalculate a visited location. 

2) Now, we perform a DFS from each cell with the current cell as (x, y). We compare the cells in the four directions (dx, dy) and skip ...read more
Answered Anonymously
Add your answer
Q2. 
Gas Station Tour Problem
You are presented with a circular track consisting of several petrol pumps. Each petrol pump is indexed from 0 to N-1 and offers certain attributes:
• The quantity of petrol ava...read more
Ans. 
Approach : 

1) We can choose every index to be our starting point and check whether we can complete the round trip starting from that index.

2) For each start point, we will run a loop starting from this index. If at any point, petrol available in the truck is not sufficient to move on to the next petrol pump, we know this is a bad starting point. So, we break the loop and try the same for the next start point.

3) As...read more
Answered Anonymously
Add your answer
Q3. 
Rabbit Jumping Problem
Consider 'n' carrots numbered from 1 to 'n' and 'k' rabbits. Each rabbit jumps to carrots only at multiples of its respective jumping factor A_j (i.e., A_j, 2A_j, 3A_j, ...), for all ra...read more
Ans. 
Approach : 

1) Create a boolean array of size n + 1 with default value false.

2) Run a loop from i=0 to k. If A[i] is marked true then we don’t need to traverse its multiples as they have been already traversed. Else Traverse all multiples of A[i] less than n. The carrots which are visited mark it true.

3) After doing traversal count the values from 1 to n with false values. Return this value.


TC : O(N * log(max(A[i])
Answered Anonymously
Add your answer