CodeSignal Technical Assessment Domain-Specific Knowledges 4

Question 1

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

Accepted Answer

Merge Sort

Answer

Merge Sort guarantees O(n log n) in all cases, whereas Quick Sort degrades to O(n²) on already-sorted input with a naive pivot.

Question 2

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

Accepted Answer

Enforcing referential integrity between two tables

Answer

A foreign key ensures that every value in the child column exists as a primary key in the parent table, preventing orphaned records.

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

CAP theorem proves that when a partition occurs, a distributed system must choose to either remain consistent (reject some requests) or available (return possibly stale data).

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

A Semaphore maintains an internal counter and blocks threads once the counter reaches zero, allowing N concurrent accesses rather than just 1.

Question 5

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

Accepted Answer

order

Answer

The CSS `order` property lets you reposition flex (or grid) items visually while their source order in the DOM remains unchanged.

Codesignal Practice Test

Codesignal Practice Test

CodeSignal Technical Assessment Domain-Specific Knowledges 4