Duolingo LeetCode Interview Questions
Duolingo has asked 5 distinct LeetCode questions across all recorded interviews: 0 easy, 3 medium and 2 hard. The questions reported most often are Encrypt and Decrypt Strings, Minimum Number of People to Teach and K Radius Subarray Averages. 1 of them was reported in interviews from the Last 3 Months window. Each question links straight to LeetCode.
| # | Problem | Difficulty | Frequency | Acceptance | |
|---|---|---|---|---|---|
| 1 | Encrypt and Decrypt Strings | Hard | 100 | 0.4% | |
| 2 | Minimum Number of People to Teach | Medium | 85 | 0.7% | |
| 3 | K Radius Subarray Averages | Medium | 83 | 0.5% | |
| 4 | Longest Increasing Path in a Matrix | Hard | 70 | 0.6% | |
| 5 | Task Scheduler II | Medium | 66 | 0.5% |
Where this data comes from
These questions come from the public leetcode-company-wise-problems data set, which collects interview reports from candidates. They are community-reported rather than published by Duolingo, so treat the list as a strong signal of what gets asked, not an official or exhaustive syllabus. Last refreshed .
How to read this list
The tabs at the top split the questions by how recently people said they were asked in interviews. "Last 30 Days" is the past month, "Last 3 Months" is the past quarter, and so on. "All Time" is every question on record for this company.
Frequency is a score from 0 to 100 for how often a question showed up in that time window. A higher number means it came up more often, so the list starts with the most common questions first. It is a relative popularity signal within Duolingo's questions, not a probability that you will be asked it. Acceptance is LeetCode's own share of submissions that pass for that problem, across all users, not something specific to Duolingo. Click any question to open it on LeetCode.