Practice real interview problems from Jane Street
| Status | Title | Solution | Practice | Difficulty | Companies | Topics |
|---|---|---|---|---|---|---|
| 1. Two Sum | Solution | Solve | Easy | Accenture+128 | ||
| 14. Longest Common Prefix | Solution | Solve | Easy | Accenture+56 | ||
| 20. Valid Parentheses | Solution | Solve | Easy | Accenture+118 | ||
| 415. Add Strings | Solution | Solve | Easy | Airbnb+14 | ||
| 495. Teemo Attacking | Solution | Solve | Easy | Amazon+4 | ||
| 2085. Count Common Words With One Occurrence | Solution | Solve | Easy | Jane Street | ||
| 2235. Add Two Integers | Solution | Solve | Easy | Accenture+9 |
Jane Street is one of the most selective quantitative trading firms in the world, known for its strong engineering culture and emphasis on deep problem solving. Engineers at Jane Street build high‑performance trading systems and infrastructure, so the hiring process strongly evaluates algorithmic thinking, mathematical intuition, and clean coding ability.
The Jane Street coding interview typically begins with an online assessment or recruiter phone screen, followed by one or more technical interviews. Candidates are asked to solve algorithmic problems while explaining their reasoning clearly. Interviewers often care as much about how you think as the final answer.
In coding rounds, Jane Street commonly tests:
The overall difficulty is usually medium to hard, with a strong emphasis on clarity, correctness, and edge‑case handling. Many questions resemble advanced competitive programming or high‑quality LeetCode problems.
To help you prepare efficiently, FleetCode has compiled 13 real Jane Street interview questions frequently reported by candidates. Each problem is organized by difficulty and includes clear explanations and solutions in Python, Java, and C++. By practicing these targeted problems, you can focus on the algorithmic patterns Jane Street interviewers care about most and build confidence before your interview.
Preparing for a Jane Street coding interview requires strong fundamentals in algorithms as well as clear communication. The company values structured thinking and expects candidates to reason carefully through problems.
Typical interview format:
Unlike many big tech companies, Jane Street sometimes mixes mathematical reasoning with algorithm design. You may encounter problems involving combinatorics, probability, or game-like scenarios that still require efficient data structures.
Most common problem categories include:
Preparation strategy:
Common mistakes to avoid:
Most candidates benefit from 6–10 weeks of focused preparation. During that time, solving 100–150 well‑chosen DSA problems and reviewing common algorithm patterns can significantly improve performance. Practicing curated problems—like the 13 Jane Street questions on FleetCode—helps you concentrate on the patterns most likely to appear in the interview.
