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Servicenow DSA Interview Questions
73 curated coding interview questions directly asked in Servicenow technical rounds, sorted by frequency with recency and difficulty diagnostics.
73
Total Questions
8 (11%)
Easy Problems
53 (73%)
Medium Problems
12 (16%)
Hard Problems
🔥 Most Tested Topics:
Arrays (21)Strings (18)Core DSA (15)Trees (6)Graphs (4)
📂 Sourced Datasets:
Last 6 monthsAll questionsOlder than 6 months
| ID | Problem | Difficulty | Topic | Pattern | Acceptance | Frequency | Recency |
|---|---|---|---|---|---|---|---|
| 146 | LRU Cache | Medium | Design | Data Structure Design | 47.4% | 100.0% | 6m |
| 122 | Best Time to Buy and Sell Stock II | Medium | Core DSA | Implementation / Reasoning | 71.1% | 87.5% | 6m |
| 1192 | Critical Connections in a Network | Hard | Graphs | BFS / DFS / Topological Sort | 59.7% | 87.5% | 6m |
| 3 | Longest Substring Without Repeating Characters | Medium | Strings; Trees | Hashing / Sliding Window; DFS / BFS; Sliding Window | 39.1% | 87.5% | all |
| 42 | Trapping Rain Water | Hard | Core DSA | Two Pointers | 67.4% | 87.5% | all |
| 200 | Number of Islands | Medium | Graphs | BFS / DFS / Topological Sort | 64.4% | 87.5% | all |
| 3106 | Lexicographically Smallest String After Operations With Constraint | Medium | Strings; Graphs | Hashing / Sliding Window; BFS / DFS / Topological Sort | 62.8% | 87.5% | all |
| 2318 | Number of Distinct Roll Sequences | Hard | Core DSA | Implementation / Reasoning | 58.1% | 87.5% | all |
| 3203 | Find Minimum Diameter After Merging Two Trees | Hard | Arrays; Trees | Sorting / Prefix / Scan; DFS / BFS | 57.0% | 87.5% | all |
| 11 | Container With Most Water | Medium | Core DSA | Two Pointers | 60.0% | 75.0% | all |
| 20 | Valid Parentheses | Easy | Strings | Hashing / Sliding Window | 44.2% | 75.0% | all |
| 22 | Generate Parentheses | Medium | Strings | Hashing / Sliding Window | 78.7% | 75.0% | all |
| 41 | First Missing Positive | Hard | Arrays | Sorting / Prefix / Scan | 42.9% | 75.0% | all |
| 121 | Best Time to Buy and Sell Stock | Easy | Core DSA | Implementation / Reasoning | 56.8% | 75.0% | all |
| 735 | Asteroid Collision | Medium | Core DSA | Implementation / Reasoning | 47.9% | 75.0% | all |
| 443 | String Compression | Medium | Strings | Hashing / Sliding Window | 60.0% | 75.0% | all |
| 239 | Sliding Window Maximum | Hard | Arrays | Sorting / Prefix / Scan; Sliding Window | 48.8% | 75.0% | all |
| 417 | Pacific Atlantic Water Flow | Medium | Core DSA | Implementation / Reasoning | 61.0% | 75.0% | all |
| 424 | Longest Repeating Character Replacement | Medium | Strings | Hashing / Sliding Window | 59.7% | 75.0% | all |
| 1 | Two Sum | Easy | Arrays | Sorting / Prefix / Scan; Two Pointers | 57.5% | 62.5% | all |
| 6 | Zigzag Conversion | Medium | Core DSA | Implementation / Reasoning | 54.2% | 62.5% | all |
| 49 | Group Anagrams | Medium | Strings | Hashing / Sliding Window | 72.6% | 62.5% | all |
| 53 | Maximum Subarray | Medium | Arrays | Sorting / Prefix / Scan | 53.3% | 62.5% | all |
| 215 | Kth Largest Element in an Array | Medium | Arrays; Heap | Sorting / Prefix / Scan; Priority Queue | 68.9% | 62.5% | all |
| 283 | Move Zeroes | Easy | Core DSA | Two Pointers | 63.8% | 62.5% | all |
| 1944 | Number of Visible People in a Queue | Hard | Stack / Queue | Monotonic Stack / Simulation | 73.1% | 62.5% | all |
| 322 | Coin Change | Medium | Dynamic Programming | State Transition | 48.4% | 62.5% | all |
| 994 | Rotting Oranges | Medium | Core DSA | Implementation / Reasoning | 58.7% | 62.5% | all |
| 186 | Reverse Words in a String II | Medium | Strings | Hashing / Sliding Window | 56.7% | 62.5% | all |
| 460 | LFU Cache | Hard | Design | Data Structure Design | 49.2% | 62.5% | all |
| 73 | Set Matrix Zeroes | Medium | Arrays | Sorting / Prefix / Scan | 62.9% | 62.5% | all |
| 2116 | Check if a Parentheses String Can Be Valid | Medium | Strings | Hashing / Sliding Window | 45.2% | 62.5% | all |
| 1963 | Minimum Number of Swaps to Make the String Balanced | Medium | Arrays; Strings | Sorting / Prefix / Scan; Hashing / Sliding Window | 78.0% | 62.5% | all |
| 45 | Jump Game II | Medium | Greedy | Greedy | 42.9% | 62.5% | all |
| 21 | Merge Two Sorted Lists | Easy | Arrays; Linked List | Sorting / Prefix / Scan; Two Pointers | 68.3% | 62.5% | all |
| 4 | Median of Two Sorted Arrays | Hard | Arrays; Heap | Sorting / Prefix / Scan; Priority Queue | 46.6% | 50.0% | all |
| 5 | Longest Palindromic Substring | Medium | Strings; Trees | Hashing / Sliding Window; DFS / BFS | 37.8% | 50.0% | all |
| 56 | Merge Intervals | Medium | Arrays | Sorting / Prefix / Scan | 51.8% | 50.0% | all |
| 2063 | Vowels of All Substrings | Medium | Strings; Trees | Hashing / Sliding Window; DFS / BFS | 55.4% | 50.0% | all |
| 152 | Maximum Product Subarray | Medium | Arrays | Sorting / Prefix / Scan | 36.4% | 50.0% | all |
| 179 | Largest Number | Medium | Core DSA | Implementation / Reasoning | 43.1% | 50.0% | all |
| 206 | Reverse Linked List | Easy | Linked List | Two Pointers | 80.6% | 50.0% | all |
| 692 | Top K Frequent Words | Medium | Strings; Heap | Hashing / Sliding Window; Priority Queue | 60.2% | 50.0% | all |
| 739 | Daily Temperatures | Medium | Stack / Queue | Monotonic Stack / Simulation | 68.7% | 50.0% | all |
| 706 | Design HashMap | Easy | Design | Data Structure Design | 66.6% | 50.0% | all |
| 1611 | Minimum One Bit Operations to Make Integers Zero | Hard | Arrays | Sorting / Prefix / Scan | 78.4% | 50.0% | all |
| 50 | Pow(x, n) | Medium | Core DSA | Implementation / Reasoning | 38.7% | 50.0% | all |
| 2385 | Amount of Time for Binary Tree to Be Infected | Medium | Trees | DFS / BFS | 65.4% | 50.0% | all |
| 2380 | Time Needed to Rearrange a Binary String | Medium | Strings | Hashing / Sliding Window | 53.0% | 50.0% | all |
| 199 | Binary Tree Right Side View | Medium | Trees | DFS / BFS | 70.2% | 50.0% | all |
| 17 | Letter Combinations of a Phone Number | Medium | Strings; Backtracking | Hashing / Sliding Window; Backtracking | 66.1% | 50.0% | all |
| 234 | Palindrome Linked List | Easy | Strings; Linked List | Hashing / Sliding Window; Two Pointers | 58.0% | 50.0% | all |
| 18 | 4Sum | Medium | Arrays | Sorting / Prefix / Scan | 40.6% | 50.0% | all |
| 227 | Basic Calculator II | Medium | Stack / Queue | Monotonic Stack / Simulation | 46.9% | 50.0% | all |
| 694 | Number of Distinct Islands | Medium | Graphs | BFS / DFS / Topological Sort | 62.8% | 50.0% | all |
| 31 | Next Permutation | Medium | Backtracking | Backtracking | 45.3% | 50.0% | all |
| 134 | Gas Station | Medium | Greedy | Greedy | 48.0% | 50.0% | all |
| 162 | Find Peak Element | Medium | Binary Search | Binary Search | 47.0% | 50.0% | all |
| 494 | Target Sum | Medium | Arrays | Sorting / Prefix / Scan | 52.2% | 50.0% | all |
| 540 | Single Element in a Sorted Array | Medium | Arrays | Sorting / Prefix / Scan | 59.3% | 50.0% | all |
| 347 | Top K Frequent Elements | Medium | Heap | Priority Queue | 66.4% | 50.0% | all |
| 992 | Subarrays with K Different Integers | Hard | Arrays | Sorting / Prefix / Scan | 68.1% | 50.0% | all |
| 213 | House Robber II | Medium | Dynamic Programming | State Transition | 44.9% | 50.0% | all |
| 2291 | Maximum Profit From Trading Stocks | Medium | Arrays | Sorting / Prefix / Scan | 48.2% | 50.0% | all |
| 560 | Subarray Sum Equals K | Medium | Arrays | Sorting / Prefix / Scan | 47.3% | 50.0% | all |
| 503 | Next Greater Element II | Medium | Stack / Queue | Monotonic Stack / Simulation | 68.4% | 50.0% | all |
| 127 | Word Ladder | Hard | Strings | Hashing / Sliding Window | 45.6% | 50.0% | all |
| 71 | Simplify Path | Medium | Core DSA | Implementation / Reasoning | 50.6% | 50.0% | all |
| 904 | Fruit Into Baskets | Medium | Core DSA | Implementation / Reasoning | 51.1% | 50.0% | all |
| 1143 | Longest Common Subsequence | Medium | Core DSA | Implementation / Reasoning | 59.2% | 50.0% | all |
| 39 | Combination Sum | Medium | Arrays; Backtracking | Sorting / Prefix / Scan; Backtracking | 76.5% | 50.0% | all |
| 151 | Reverse Words in a String | Medium | Strings | Hashing / Sliding Window | 56.4% | 50.0% | all |
| 75 | Sort Colors | Medium | Arrays | Sorting / Prefix / Scan | 69.6% | 50.0% | all |