Launching soon! The AI-powered interview tool – See it in action
Launching soon! AI-powered interview tool – View demo
N-Queens Test | Pre-employment assessment - Testlify
Back to Test Library

N-Queens Test

Overview of N-Queens Test

The "n-queens" problem involves placing "n" chess queens on an "n x n" board so they don't threaten each other. backtracking and optimization techniques are used to find solutions. this problem has applications in algorithms, optimization.

Skills measured

  • recursion
  • backtracking

Available in

English

Type

Coding Test


Time

20 Mins


Level

Intermediate


Questions

1

Use of N-Queens test

The solution approach of "N-Queens" problem is using backtracking. The goal is to find all distinct solutions for placing "N" queens on an "N x N" chessboard without any queen threatening another. The solution utilizes a depth-first search approach to explore possible configurations efficiently.

The function solveNQueens takes an integer n as input and returns a vector of vectors of strings representing the solutions. The backtrack function is used to perform the actual exploration.

In the backtrack function, the algorithm iterates through each column in the current row r. It checks whether placing a queen at the current position is valid, considering the constraints of not sharing the same column or diagonals with other queens. If the position is valid, the queen is placed, and the corresponding flags are updated to mark the occupied columns and diagonals.

The recursion continues to the next row, and the process repeats. When all queens are placed successfully, a valid solution is found and added to the result vector.

If a solution isn't possible in the current configuration, the algorithm backtracks by resetting the board, column, and diagonal flags to their previous state, allowing the algorithm to explore other possibilities.

The solveNQueens function returns a vector containing all solutions, where each solution is represented by a vector of strings, indicating the queen positions on the board.

Relevant for

  • Software Developer Engineer
  • Software Developer
  • Software Engineers

Hire the best,
every time,
anywhere


4.8

Customer satisfaction

Testlify helps you identify the best talent from anywhere in the world, with a seamless experience that candidates and hiring teams love every step of the way.

1

recursion

Recursion is a crucial skill covered in the N-Queens problem, as it allows us to break down the problem into smaller, more manageable subproblems. By defining a recursive function to place queens on the board one by one, we can explore all possible solutions and backtrack when a dead end is reached. This technique is important in solving complex problems efficiently, as it eliminates the need for nested loops and reduces the amount of code required. Recursion also helps in improving the readability and maintainability of the code, making it easier to understand and debug.

2

backtracking

Backtracking is a crucial skill covered in the N-Queens problem, as it allows for the efficient exploration of all possible solutions. By systematically trying different arrangements of queens on the chessboard and backtracking when a dead-end is reached, the algorithm can quickly eliminate invalid configurations and focus on finding the correct solution. This approach helps in reducing the time complexity of the problem and ensures that all possible solutions are considered. Overall, mastering the backtracking skill is essential for solving complex problems like N-Queens efficiently and effectively.

The N-Queens test is created by a subject-matter expert

Testlify’s skill tests are designed by experienced SMEs (subject matter experts). We evaluate these experts based on specific metrics such as expertise, capability, and their market reputation. Prior to being published, each skill test is peer-reviewed by other experts and then calibrated based on insights derived from a significant number of test-takers who are well-versed in that skill area. Our inherent feedback systems and built-in algorithms enable our SMEs to refine our tests continually.

subject matter expert

Why choose Testlify

Elevate your recruitment process with Testlify, the finest talent assessment tool. With a diverse test library boasting 1500+ tests, and features such as custom questions, typing test, live coding challenges, Google Suite questions, and psychometric tests, finding the perfect candidate is effortless. Enjoy seamless ATS integrations, white-label features, and multilingual support, all in one platform. Simplify candidate skill evaluation and make informed hiring decisions with Testlify.

Frequently Asked Questions (FAQs)

Want to know more about Testlify? Here are answers to the most commonly asked questions about our company

Yes, Testlify offers a free trial for you to try out our platform and get a hands-on experience of our talent assessment tests. Sign up for our free trial and see how our platform can simplify your recruitment process.

To select the tests you want from the Test Library, go to the Test Library page and browse tests by categories like role-specific tests, Language tests, programming tests, software skills tests, cognitive ability tests, situational judgment tests, and more. You can also search for specific tests by name.

Ready-to-go tests are pre-built assessments that are ready for immediate use, without the need for customization. Testlify offers a wide range of ready-to-go tests across different categories like Language tests (22 tests), programming tests (57 tests), software skills tests (101 tests), cognitive ability tests (245 tests), situational judgment tests (12 tests), and more.

Yes, Testlify offers seamless integration with many popular Applicant Tracking Systems (ATS). We have integrations with ATS platforms such as Lever, BambooHR, Greenhouse, JazzHR, and more. If you have a specific ATS that you would like to integrate with Testlify, please contact our support team for more information.

Testlify is a web-based platform, so all you need is a computer or mobile device with a stable internet connection and a web browser. For optimal performance, we recommend using the latest version of the web browser you’re using. Testlify’s tests are designed to be accessible and user-friendly, with clear instructions and intuitive interfaces.

Yes, our tests are created by industry subject matter experts and go through an extensive QA process by I/O psychologists and industry experts to ensure that the tests have good reliability and validity and provide accurate results.

Hire with Facts, not Fiction.

Resumes don’t tell you everything! Testlify gives you the insights you need to hire the right people with skills assessments that are accurate, automated, and unbiased.

©2024 Testlify All Rights Reserved

Please enable JavaScript in your browser to complete this form.
Name

4.8

[fluentform id=”23″]

Get 40% off on your first year’s billing!

Hurry and make the most of this special offer before it expires.

New customers only.

[fluentform id=”21″]

Test library request

These are upcoming tests. If you wish to prioritize this test request, we can curate it for you at an additional cost.

Please enable JavaScript in your browser to complete this form.
No settings found for the grid #1.