SACHA Engineering Senior Project Engineer Interview Questions and Answers

90 minute test on hacker rank consisting of 3 coding questions all of medium difficulty. Most candidates are required to solve more than 1 question.

Q1. Questions on concepts of OOPS and Operating Systems.
Add your answer
Q2. Find least common ancestor of a binary tree.
Ans. 
Find the lowest common ancestor of a binary tree.
• Traverse the tree recursively from the root node.

• If the current node is null or matches either of the given nodes, return the current node.

• Recursively search for the nodes in the left and right subtrees.

• If both nodes are found in different subtrees, return the current node.

• If both nodes are found in the same subtree, continue the search in that subtree.
Answered by AI
Add your answer
Q3. Find first missing positive integer from an array for non-negative integers.
Ans. 
Find first missing positive integer from an array of non-negative integers.
• Create a hash set to store all positive integers in the array

• Loop through the array and add all positive integers to the hash set

• Loop through positive integers starting from 1 and return the first missing integer not in the hash set
Answered by AI
Add your answer

Q1. Design a parking lot
Ans. 
Design a parking lot
• Consider the size and capacity of the parking lot

• Decide on the layout and organization of parking spaces

• Implement a system to manage parking availability and reservations

• Include features like ticketing, payment, and security

• Consider scalability and future expansion
Answered by AI
Add your answer

Q1. Given a grid which represents an ocean( For all index i,j if mat[i][j] = 1 is island and mat[i][j] = 0 means water). Find the island with largest area.
Add your answer
Q2. Given list of strings group them into distinct anagrams.
Ans. 
Group list of strings into distinct anagrams.
• Create a hash table with sorted string as key and list of anagrams as value.

• Iterate through the list of strings and add each string to its corresponding anagram list in the hash table.

• Return the values of the hash table as a list of lists.
Answered by AI
Add your answer

Round duration - 40 minutes
Round difficulty - Medium

Asked about time complexity of algorithm, puzzles, DBMS, cutting edge technologies etc. What are indexes?

Q1. 
Flip Bits Problem Explanation
Given an array of integers ARR of size N, consisting of 0s and 1s, you need to select a sub-array and flip its bits. Your task is to return the maximum count of 1s that can b...read more
Ans. 
Given an array of 0s and 1s, find the maximum count of 1s by flipping a sub-array at most once.
• Iterate through the array and keep track of the maximum count of 1s obtained by flipping a sub-array.

• Consider flipping a sub-array from index i to j and calculate the count of 1s in the resulting array.

• Return the maximum count of 1s obtained by flipping a sub-array at most once.
Answered by AI
Add your answer

Round duration - 20 minutes
Round difficulty - Medium

Asked 1 standard algorithm

Q1. 
Number of Islands Problem Statement
You are provided with a 2-dimensional matrix having N rows and M columns, containing only 1s (land) and 0s (water). Your goal is to determine the number of islands in t...read more
Ans. 
Count the number of islands in a 2D matrix of 1s and 0s.
• Iterate through the matrix and perform depth-first search (DFS) to find connected 1s.

• Mark visited cells to avoid redundant traversal.

• Increment island count whenever a new island is encountered.
Answered by AI
Add your answer

Dont't remember the exact questions

Q1. Previous projects questions
Add your answer
Q2. Data structure and algo questions
Add your answer

Simple DBMS and DSA Questions

Q1. String Manipulations
Add your answer
Q2. Linked lists questions
Add your answer

Coding round consisting DSA portion mainly.

Q1. SQL questions on Joins
Add your answer
Q2. Problems given on Hacker rank
Add your answer

Q1. Sorting related questions
Add your answer
Q2. Tell me about yourself, family background, hobbies
Add your answer