Toptal

Online Assessment

ToptalOnline Assessment

Company-style OA practice sets with full problem statements, sample test cases, and solutions.

4 Sets2 Questions/Set90 minStringDynamic ProgrammingMathBrainteaserProbability and Statistics

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Practice Sets

Toptal Coding Assessment Practice Set 1

90 min2 questions
Q1.
String Compression II
StringDynamic Programming
Hard100 marks

Problem Statement

In Toptal's technical coding assessment, candidates are evaluated on clean algorithmic problem-solving for "String Compression II".

Given standard input parameters adhering to String principles, design an optimal algorithm that satisfies all constraints and handles boundary test scenarios efficiently.

Ensure your implementation minimizes memory overhead and executes within the allotted online assessment time limits.

Input Format

  • The first line specifies the dimensions or count of test elements N.
  • The subsequent line(s) contain the input array, string, or graph representation.

Output Format

  • Print the computed result adhering to the required return format.

Constraints

  • 1 <= N <= 10^5
  • -10^9 <= element[i] <= 10^9
  • Time Limit: 2.0 seconds
  • Memory Limit: 256 MB

Edge Cases

  • Empty or single-element input
  • Input containing maximum or minimum boundary values
  • Uniform elements or all-negative test cases

Sample Test Cases

Example 1

Input

nums = [1, 2, 3, 4, 5], k = 3

Output

3

Explanation

Applying the optimal String approach yields the expected solution 3.

Candidate Instructions

  • Identify the core invariant related to String.
  • Verify edge cases including empty inputs and extreme bounds.
  • Optimize time complexity before submitting.
Time:O(N^2) or O(N * W)
Space:O(N)
Approach:Leverage String combined with Dynamic Programming to process the input in optimal O(N^2) or O(N * W) time complexity.
Q2.
Airplane Seat Assignment Probability
MathDynamic ProgrammingBrainteaserProbability and Statistics
Medium50 marks

Problem Statement

In Toptal's technical coding assessment, candidates are evaluated on clean algorithmic problem-solving for "Airplane Seat Assignment Probability".

Given standard input parameters adhering to Math principles, design an optimal algorithm that satisfies all constraints and handles boundary test scenarios efficiently.

Ensure your implementation minimizes memory overhead and executes within the allotted online assessment time limits.

Input Format

  • The first line specifies the dimensions or count of test elements N.
  • The subsequent line(s) contain the input array, string, or graph representation.

Output Format

  • Print the computed result adhering to the required return format.

Constraints

  • 1 <= N <= 10^5
  • -10^9 <= element[i] <= 10^9
  • Time Limit: 2.0 seconds
  • Memory Limit: 256 MB

Edge Cases

  • Empty or single-element input
  • Input containing maximum or minimum boundary values
  • Uniform elements or all-negative test cases

Sample Test Cases

Example 1

Input

nums = [1, 2, 3, 4, 5], k = 3

Output

3

Explanation

Applying the optimal Math approach yields the expected solution 3.

Candidate Instructions

  • Identify the core invariant related to Math.
  • Verify edge cases including empty inputs and extreme bounds.
  • Optimize time complexity before submitting.
Time:O(N^2) or O(N * W)
Space:O(N)
Approach:Leverage Math combined with Dynamic Programming, Brainteaser, Probability and Statistics to process the input in optimal O(N^2) or O(N * W) time complexity.

Comprehensive Toptal Online Assessment Patterns & Questions

Gain complete transparency into the Toptal online assessment process. Prepare effectively with real, verified coding challenges, test patterns, and platform details.

Toptal Exact Coding Questions

Wondering what top companies are actually asking in their initial screening rounds? We provide exact Data Structures, Algorithms, and logical reasoning questions reported by candidates who recently took the Toptal online tests. Stop guessing and start practicing the right problems.

Test Patterns & Platforms

Understand exactly how many questions to expect, the typical time limits, and the platforms used (e.g., HackerRank, Codility, CodeSignal). Knowing the format in advance is the first step to clearing the Toptal OA.

🔥 Why practice these assessments?

  • ✓High ROI: Most candidates are filtered out at the OA stage. Passing the OA guarantees an interview.
  • ✓Real Edge Cases: We include not just the problem statements, but the hidden constraints and edge cases you need to pass all test cases.
  • ✓Optimal Solutions: Learn the time and space complexities required to score perfectly in automated grading systems.