Microsoft - 1 Month Prep Roadmap
For candidates with existing DSA foundation who need focused Microsoft-specific prep. ~3-4 hours/day | 6 days/week
Microsoft interview flow: OA -> 3 Tech Rounds (DSA + LLD + HLD) -> AA (Behavioral) Round
Week 1: DSA Core (Most Asked Topics)
Focus: Trees + Graphs (Microsoft's #1 and #2 topics)
| Day | Task | Problems |
|---|---|---|
| 1 | Tree BFS fundamentals | Binary Tree Level Order Traversal (6x), Binary Tree Zigzag Level Order Traversal (asked 8x), Binary Tree Right Side View (4x) |
| 2 | Tree DFS + BST | Lowest Common Ancestor of a Binary Tree (asked 8x), Validate Binary Search Tree (asked 6x), Kth Smallest Element in a BST (5x) |
| 3 | Tree construction + hard | Construct Binary Tree from Preorder and Inorder Traversal (asked 8x), Serialize and Deserialize Binary Tree (5x), Binary Tree Maximum Path Sum (5x) |
| 4 | Graph BFS/DFS | Number of Islands (asked 14x), Rotting Oranges (asked 7x), Max Area of Island (4x) |
| 5 | Graph Topological Sort | Course Schedule II (asked 11x), Course Schedule (asked 7x), Alien Dictionary (4x) |
| 6 | Graph advanced | Critical Connections in a Network (6x), Network Delay Time (5x), Cheapest Flights Within K Stops (5x) |
Course: Graph Course | Tree Course
Week 2: DSA Core (DP + Data Structures + Intervals)
Focus: DP + Intervals + Stack/Queue + Design (Microsoft's #3-#6 topics)
| Day | Task | Problems |
|---|---|---|
| 1 | DP fundamentals | Climbing Stairs (5x), Decode Ways (asked 6x), Jump Game (asked 7x), Word Break (5x) |
| 2 | DP sequences + intervals | Longest Increasing Subsequence (4x), Coin Change (4x), Meeting Rooms II (asked 12x), Merge Intervals (7x) |
| 3 | Stack / Queue | Valid Parentheses (asked 10x), Generate Parentheses (6x), Basic Calculator II (4x), Daily Temperatures (3x) |
| 4 | HashMap / Design | LRU Cache (asked 15x), Group Anagrams (asked 8x), Insert Delete GetRandom O(1) (2x) |
| 5 | Array / Two Pointers | Two Sum (8x), Container With Most Water (8x), 3Sum (8x), Trapping Rain Water (7x) |
| 6 | Binary Search + Linked List | Search in Rotated Sorted Array (asked 11x), Reverse Linked List (7x), Add Two Numbers (6x), Merge k Sorted Lists (7x) |
Course: DP Course | Greedy Course -> Intervals | Mono Stack | Binary Search
Week 3: LLD + HLD
Focus: Pseudocode-level design (Microsoft-style) + Top System Design
| Day | Task | Details |
|---|---|---|
| 1 | LLD: Parking Lot (asked 6x) | Multi-floor, spot types, Strategy + Factory patterns. Pseudocode with class diagrams. Focus on SOLID. |
| 2 | LLD: Cache with Pluggable Eviction (asked 3x) | Strategy pattern for LRU/LFU/FIFO. Interface-first design. Show Open/Closed principle. |
| 3 | LLD: Notification System (asked 4x) | Observer pattern, Builder for notification construction. Channel selection via Strategy. |
| 4 | LLD: Board Game -- Snake & Ladder or Ludo (asked 3x) | State pattern for game state, Command for moves, Template for game loop. |
| 5 | HLD: URL Shortener (asked 5x) | Hashing, read-heavy caching, DB sharding, multi-region deployment, rate limiting. |
| 6 | HLD: Notification System (asked 5x) + Chat Application (asked 4x) | Fan-out, message queue, WebSocket, push notifications, delivery receipts. |
Course: LLD Course | System Design
Week 4: Mock Interviews + Behavioral (AA Round) + Gaps
| Day | Task | Details |
|---|---|---|
| 1 | HLD: Monitoring/Alert System (asked 4x) + Cache/KV Store (asked 4x) | Time-series DB, alerting rules, consistent hashing, eviction. |
| 2 | LLD: Rate Limiter (3x) + Undo/Redo Mechanism | Token bucket, Strategy pattern, Command + Memento for undo/redo. |
| 3 | AA Round Prep: Prepare 5 STAR stories | Focus on: collaboration, handling ambiguity, growth mindset, customer impact, conflict resolution. Microsoft's AA round checks culture fit and growth mindset. |
| 4 | Mock: Full DSA mock (2 problems, 45 min) | Pick from top problems. Communicate approach before coding. |
| 5 | Mock: Full LLD mock (1 problem, 60 min) | Requirements -> Class diagram -> Pseudocode -> Extensibility discussion. |
| 6 | Mock: Full HLD mock (1 problem, 60 min) | Requirements -> API -> Data model -> Architecture -> Deep dive -> Trade-offs. |
Problem Count
| Category | Count |
|---|---|
| DSA problems solved | ~35 |
| LLD problems practiced | 5-6 |
| HLD problems practiced | 5-6 |
| AA (behavioral) stories prepared | 5 |
Microsoft-Specific Tips
- Trees dominate -- 154 Tree problems in the dataset (more than any other topic). LCA, level-order, zigzag, and BST validation are asked repeatedly.
- LRU Cache is #1 -- Asked 15 times. Know the DLL + HashMap implementation so well you can write it in your sleep.
- Mediums over Hards -- ~50% of Microsoft questions are Medium. Don't over-index on Hard problems.
- LLD = pseudocode + class diagrams -- Unlike Uber, Microsoft does not require fully runnable code. Focus on clean design, SOLID principles, and extensibility.
- AA Round is behavioral -- "As Appropriate" round. Growth mindset, collaboration, handling failure. Use STAR format. Microsoft explicitly evaluates culture fit.
- Communication wins -- Talk through your approach before writing code. Microsoft values structured thinking and collaboration.
- Don't optimize prematurely -- Start with brute force, discuss complexity, then optimize. Interviewers want to see your problem-solving process.