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Blackrock DSA Interview Questions
14 curated coding interview questions directly asked in Blackrock technical rounds, sorted by frequency with recency and difficulty diagnostics.
14
Total Questions
6 (43%)
Easy Problems
7 (50%)
Medium Problems
1 (7%)
Hard Problems
🔥 Most Tested Topics:
Arrays (6)Strings (4)Trees (3)Core DSA (2)Graphs (1)
📂 Sourced Datasets:
Last 6 monthsAll questionsOlder than 6 months
| ID | Problem | Difficulty | Topic | Pattern | Acceptance | Frequency | Recency |
|---|---|---|---|---|---|---|---|
| 202 | Happy Number | Easy | Core DSA | Implementation / Reasoning | 59.7% | 100.0% | 6m |
| 3068 | Find the Maximum Sum of Node Values | Hard | Arrays; Trees | Sorting / Prefix / Scan; DFS / BFS | 69.4% | 75.0% | all |
| 49 | Group Anagrams | Medium | Strings | Hashing / Sliding Window | 72.6% | 62.5% | all |
| 3004 | Maximum Subtree of the Same Color | Medium | Arrays; Trees | Sorting / Prefix / Scan; DFS / BFS | 58.8% | 62.5% | all |
| 20 | Valid Parentheses | Easy | Strings | Hashing / Sliding Window | 44.2% | 50.0% | all |
| 121 | Best Time to Buy and Sell Stock | Easy | Core DSA | Implementation / Reasoning | 56.8% | 50.0% | all |
| 2291 | Maximum Profit From Trading Stocks | Medium | Arrays | Sorting / Prefix / Scan | 48.2% | 50.0% | all |
| 200 | Number of Islands | Medium | Graphs | BFS / DFS / Topological Sort | 64.4% | 37.5% | all |
| 5 | Longest Palindromic Substring | Medium | Strings; Trees | Hashing / Sliding Window; DFS / BFS | 37.8% | 37.5% | all |
| 1 | Two Sum | Easy | Arrays | Sorting / Prefix / Scan; Two Pointers | 57.5% | 37.5% | all |
| 268 | Missing Number | Easy | Arrays | Sorting / Prefix / Scan | 72.0% | 37.5% | all |
| 70 | Climbing Stairs | Easy | Dynamic Programming | State Transition | 54.1% | 37.5% | all |
| 12 | Integer to Roman | Medium | Strings | Hashing / Sliding Window | 71.0% | 37.5% | all |
| 287 | Find the Duplicate Number | Medium | Arrays | Sorting / Prefix / Scan | 64.3% | 37.5% | all |