CodeSignal Technical Assessment Domain-Specific Knowledges 4

Question 1

Which sorting algorithm has the best worst-case time complexity?

Accepted Answer

Merge Sort

Answer

Quick Sort

Answer

Bubble Sort

Answer

Insertion Sort

Question 2

In a relational database, what is a foreign key constraint used for?

Accepted Answer

Enforcing referential integrity between two tables

Answer

Speeding up JOIN operations

Answer

Encrypting values in the referenced column

Answer

Partitioning large tables across shards

Question 3

What does the CAP theorem state about distributed systems?

Accepted Answer

In the presence of a network partition, a system must trade off between Consistency and Availability

Answer

A system can achieve Consistency, Availability, and Partition tolerance simultaneously

Answer

Partitioned networks always restore within milliseconds, making CAP irrelevant in practice

Answer

Consistency and Availability can be tuned independently of network reliability

Question 4

Which concurrency primitive in Python's threading module is used to limit simultaneous access to a shared resource to a fixed number of threads?

Accepted Answer

Semaphore

Answer

Lock

Answer

Event

Answer

Condition

Question 5

In CSS, which property controls the order in which flex items appear visually without changing the DOM order?

Accepted Answer

order

Answer

z-index

Answer

flex-direction

Answer

align-self

Question 6

What is a 'deadlock' in concurrent programming?

Accepted Answer

Two or more threads permanently blocked, each waiting for a resource held by another

Answer

A thread that never releases the CPU due to an infinite loop

Answer

A race condition where two threads write the same memory location

Answer

A thread waiting indefinitely because a semaphore is never signaled

Question 7

In computer networks, what is the purpose of NAT (Network Address Translation)?

Accepted Answer

Mapping private IP addresses to one or more public IPs to conserve address space

Answer

Encrypting packets between routers

Answer

Routing packets along the shortest path

Answer

Assigning dynamic IPs to hosts via broadcast