Key Focus Areas from CRED's Job Description Data Structures: Arrays, Trees, Graphs, Heaps, Hash Tables Algorithms: Recursion, Dynamic Programming, Sorting, Graph Traversal Discrete Math: Probability, Combinatorics APIs & Testing: Edge case identification, REST principles Bonus: AI tools for coding efficiency (e.g., GitHub Copilot) Most Probable OA Question Types 1. Coding Problems (80-90% weightage) Arrays/Heaps: Find Kth largest element (Heap) Maximum subarray sum (Kadane’s algorithm) Merge overlapping intervals Trees/Graphs: Binary tree level-order traversal Shortest path in unweighted graph (BFS) Detect cycle in directed graph Dynamic Programming: Coin change problem Longest increasing subsequence (LIS) 0/1 Knapsack variations Probability/Combinatorics: Dice roll simulations (e.g., probability of sum=10 with 2 dice) Counting permutations/combinations (e.g., unique paths in a grid) 2. API Design & Testing (10-20% weightage) Design REST endpoints for a credit-score system Identify edge cases for a payment-refund API Write test cases for a wallet-balance function 3. AI Tools (Bonus Section) Optimize a given code snippet using AI tools Debug a faulty function with ChatGPT