⏱ 0:00est. 7 min
Oracle
// 1) How will you design a parking system?
// 2) Connect all 1s to make an insland in NxN matrix.
// 3) Design a project of candidate/recruiter management system in which one candidate will be assigned to only one recruiter but one recruiter can have multiple candidates. I was asked to create this using Sinatra framework + Backbonejs
// 4)CEO Round:- why would you like to work at hackerrank, why you wan't to leave your current org.
// I was asked to designed a algo which will help user to identify safe position to put the marble condition is there should be a marble in up, down , left,right direction irrespective to row, column.
// Leetcode medium/hard + front end coding challenge (Javascript+Ajax)
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Coding question : Leetcode medium (No of islands)
System design: Employer HR management web portal
Questions on data structures mostly linked list
Java, Springboot, SQl based questions in first round. 1 LLD question in second round.
theoretical questions on multithreading
bstraction ,oops concepts and example Deep knowledge on pointers in CPP, pointer manipulation, arithmetic,bit field
Lambda pointers
Longest substring with no repeating characters.
First unique character in a string
Find Linked list is palindrome or not, was able to crack with array (in place of stack, basically same).
Q1. Write the code for the following pseudocode and explain how it work * Initialize: * max_so_far 0 max_ending_here 0 // initialized to zero * Loop for each element of the array // integer array, iterating over the array, 0 < arr <1000 * (a) max_ending_here = max_ending_here + a[i] // counting the array values on every iteration, 1, 2, 3, 4, -11 => 1, 3, 6, 10, -1 * (b) if (max_ending_here < 0) max_ending_here = 0 // 0 * (c) if (max_so_far < max_ending_here) max_so_far = max_ending_here // 1, 3, 6, 10 => 10 * * return max_so_far
design a file system, React, HTML & CSS
Given an array representing a preorder tree, return the root of the tree.
Design a logging system
Describe layer 3,4,7 of OSI model
Design a mini url cloud system
Given a social media map representing each person and a list of its friends, return a list of list of all levels of a given person
There were a lot more questions in networking, rest api and design, but honestly i can't remember all.
flood fill
kth smallest in row wise column wise sorted arry
design a system that crawling site, persist a pages content of all links and sublinks. Make it robust, monitored, scalable.
with given list of nums and number of buckets, return a list with numbers distributed by those buckets
Implement hashmap
Load balancer
Find the distance of 2 leave node in a tree
word count question, dictionary problem
what is Singleton write the code of Singleton
what is Linked Hash Map how it is working write the code of it
Create an algorithm to add together two infinitely large numbers.
Implement an LRU cache.
Provide design for a vending machine
Implement a queue using a stack.
Magic Square problem
Segregate 0s and 1s from array
Java basic and collection framework, multi-threading, working of linked list, hash set
Spring boot architecture, why micro-service, when to use when not to
Circular Queue implementation
Search max element from Binary Tree
Find the duplicate number in an array of size N where the values are all between 1-N.
1. Singleton class - can we call a copy constructor or an assignment operator 2. 10 boxes contain mini boxes weighing 20kg each. 1 box contains mini boxes weighing 19kg. Find this box. 3. Write your own string class. 4. Can a constructor throw an exception 5. Can a destructor throw an exception 6. How would you know if a core file belongs to your exe 7. Reverse a string without using while or for loop 8. How are callbacks invoked 9. What is the entry point for a shared object or a DLL 10. Find if a number(not a string) is a palindrome or not. 11. Write the abs function for integer 12. How negative numbers are represented in memory(2s compliment) 13. Find out if a tree is symmetric( mirror image with root node as the axis)
How would you design the system that handle large data set? What approach would you take and what will be the pro/cons of such approach.
How do you update an array of 'n' elements with one operation ( order of 1 )
Note: Looping array is not a solution as you need to update all the values in single operation
What is IPv6 and the differences vs IPv4.
Write the structure of System.out.println
Without using length and size function how could you get the 2nd last variable in an array of integers?
How will you implement security in a web based application based on roles?
write java program to Find which first array element is not present in Second array?
1.Write ta program evalute conversion postfix to infix in java. 2.What is recursion? 3.why loop is better than recursion? 4. Write a program reverse a string with using recursion. 5. Design a class template for school exam.
Difference between Spring and struts Difference between Jsp and Javascript Difference between Jquery and Javascript Difference between Java and J2ee Parse arraylist with enhanced for loop
lot of questions on string matching
BINARY SEARCH TREE
Permutations of string
Questions on BST, Scheduling, String operations and system design.
Travelling Salesman problem , Discussion of trees / Graphs and their implementation.
I was given share prices for 10 dates and asked to write logic to find out the maximum profit,buying should happen first.
Anagram program in java
how to do a binary search
1. How to swap two numbers without using third variable. 2. Explain Collection framework 3. How to configure init params in web- inf
How to find the singly linked list is circular using only one pointer
Questions were all java related: 1) static in java 2) multithreading - lock related api and methods 3) multiple inheritance, access modifiers 4) states of threads 5) communication () of threads 6) collection related questions. Problem related to hashmap 7) sql queries on outer join and inner join 8) rest web service problem 9) tic tac toe problem thats most of them i remember.
How do the COMMIT and ROLLBACK work under the wraps?
How do you handle a situation when you got a lot to finish and you are sure to miss the dead line?
How do you optimize INSERT query where we need to insert millions of rows of data very frequently?
You have 10 boxes of balls (each ball weighing exactly10 gm) with one box with defective balls (each one of the defective balls weigh 9 gm). You are given an electronic weighing machine and only one chance at it. How will find out which box has the defective balls?
Design a code repo system? Java Core concepts Database optimizations
Implement the interator of the binary search tree.
Find 2 or more missing numbers in a set of 100 natural numbers
Design a Cache Control in java specifying what would be exposed in an interface and what would contribute to an abstract class
How do u count all nodes in the tree
Weblogic Architecture, Side by Side Deployment, JMS (Queue/Topic)
Which data structure is one of the most common source of Java memory leaks?
Given two sorted integer arrays, how do you combine them into one sorted array?
K - Rotate a word. e.g ABCDEF when 3-rotated will become DEFABC
Architecure of banking systems involving Message Broker and Process server.
First round was fair and quick, asked me difference between String x = "abc" and String y = new String("abc"); A
How does a B+ tree index work?
Considering a 2-dimension matrix that can only be traversed by 1 adjacent position at a time and never diagonally. Create an algorithm to traverse that matrix from its upper-left corner to its lower-right corner using the shorter possible path in the most efficient way.
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