Petrus Technologies Software Engineer Interview Questions and Answers

C and Golang related questions, 2 Hours assement, The test involved writing code by hand in paper in the office (Bengaluru)

Q1. Write a go code to remove duplicate elements from a slice.
Ans. 
Go code to remove duplicate elements from a slice of strings
• Use a map to keep track of unique elements

• Iterate over the slice and add elements to the map

• Create a new slice with unique elements from the map
Answered by AI
Add your answer
Q2. Difference between array and slice in Go.
Ans. 
Arrays have fixed length, slices are dynamic and can grow/shrink. Slices are references to arrays.
• Arrays have fixed length, specified at compile time.

• Slices are dynamic, can grow or shrink at runtime.

• Slices are references to arrays, allowing for more flexibility.

• Example: var arr [3]string // array with fixed length of 3

• Example: slice := make([]string, 0) // slice with dynamic length
Answered by AI
Add your answer
Q3. Explain struct and interface
Ans. 
Struct is a user-defined data type that groups related data fields together. Interface defines a set of methods that a type must implement.
• Struct is used to create complex data structures by grouping related data fields together.

• Interface defines a set of methods that a type must implement. It allows for polymorphism in Go.

• Example: type Person struct { Name string; Age int }

• Example: type Shape interface { Area() float6...read more
Answered by AI
Add your answer
Q4. What is containerization.
Add your answer
Q5. Write a go code to implement struct.
Ans. 
Implementing a struct in Go code
• Define a struct using the 'type' keyword

• Add fields to the struct with their respective data types

• Access struct fields using dot notation
Answered by AI
Add your answer
Q6. Explain goroutine.
Add your answer
Q7. How do you achieve concurrency in Go?
Ans. 
Concurrency in Go is achieved using goroutines and channels.
• Use goroutines to run functions concurrently

• Communicate between goroutines using channels

• Avoid using shared memory for synchronization
Answered by AI
Add your answer
Q8. What is channel in Go? What are the differences between buffered and unbuffered channel?
Ans. 
A channel in Go is a communication mechanism that allows goroutines to communicate with each other.
• Buffered channels have a specific capacity and can send multiple values without the need for a corresponding receive operation immediately.

• Unbuffered channels have no capacity and require both a send and receive operation to be ready at the same time for communication to occur.
Answered by AI
Add your answer
Q9. What is scaling? Horizontal and vertical scaling.
Ans. 
Scaling refers to the ability of a system to handle increasing amounts of work or its potential to accommodate growth.
• Horizontal scaling involves adding more machines to distribute the load, while vertical scaling involves increasing the resources of a single machine.

• Horizontal scaling is more cost-effective and provides better fault tolerance, but can be more complex to implement.

• Vertical scaling is simpler to impleme...read more
Answered by AI
Add your answer

There are three sections: -
1. Quants
2. English
3. Reasoning
All sections are accessible medium but you have maintained the speed and accuracy.
after that coding snippet are in java/python.

Code snippets are there in coding sections.

Q1. Question on linkedlist, remove duplicates
Add your answer
Q2. House robber 2,3
Add your answer

Q1. DBMS: Indexing Python: Monkey Patching
Add your answer

Basic concept with an example.

Q1. Algorithm and design
Add your answer

Leetcode practice should be sufficient to tackle this round.

Q1. Trapping Rain Water problem.
Add your answer

3 questions, medium hard

Q1. Greedy Algorithm, simple jumps question, easily approachable by greedy algorithm
Add your answer
Q2. Binary Search, simple array based
Add your answer

Q1. DBMS, Projects, SQL Queries
Add your answer
Q2. 2 coding questions
Add your answer

There were 13 MCQ questions on DSA, 17 MCQ aptitude questions, and 2 coding questions.

Q1. There's a string s1,s2 and s3. s1 and s2 are divided into n and m parts respectively. check if, after interleaving strings s1 and s2, we get s3 as one of the answers.
Ans. 
Check if after interleaving strings s1 and s2, we get s3 as one of the answers.
• Create a recursive function to check all possible interleavings of s1 and s2

• Check if the current interleaving matches s3

• Return true if a valid interleaving is found, false otherwise
Answered by AI
Add your answer
Q2. Difference between cluster and non-cluster indexing. Do you know about database indexing?
Ans. 
Cluster indexing physically reorders the data on disk to match the index, while non-cluster indexing does not.
• Cluster indexing physically reorders the data on disk to match the index structure, leading to faster retrieval of data.

• Non-cluster indexing creates a separate data structure that points to the actual data, which may result in slower retrieval times.

• Cluster indexing is typically used in primary keys, while non-...read more
Answered by AI
Add your answer
Q3. Difference between stack and heap memory.
Add your answer
Q4. What is a stable sort?
Ans. 
A stable sort is a sorting algorithm that preserves the relative order of equal elements in the sorted output.
• Stable sorts are useful when the original order of equal elements needs to be maintained.

• Examples of stable sorting algorithms include Merge Sort, Bubble Sort, and Insertion Sort.

• In a stable sort, if two elements have the same key value, their relative order in the original array is preserved in the sorted arra...read more
Answered by AI
Add your answer
Q5. What's the time complexity of insertion in a hashmap?
Add your answer
Q6. What is hashing?
Ans. 
Hashing is a process of converting input data into a fixed-size string of bytes using a hash function.
• Hashing is used to securely store passwords by converting them into a hash value.

• Hashing is used in data structures like hash tables to quickly retrieve data based on a key.

• Common hash functions include MD5, SHA-1, and SHA-256.
Answered by AI
Add your answer