Coding Interview Questions

⏱ 8 min read Heaps (priority queues) are the go-to data structure for problems involving the K-th largest/smallest element, merging sorted sequences, and scheduling […] Read article

⏱ 7 min read Prefix sum is one of the most versatile techniques in competitive programming and coding interviews. It transforms O(N) range queries Read article

⏱ 7 min read Sorting is the most fundamental algorithmic operation — it appears directly in interview questions and as a building block for Read article

⏱ 7 min read Greedy algorithms make the locally optimal choice at each step, hoping to find the global optimum. Unlike dynamic programming which Read article

⏱ 8 min read Binary search is deceptively simple in concept but tricky in implementation. Off-by-one errors, wrong boundary conditions, and infinite loops are Read article

⏱ 6 min read Union-Find (Disjoint Set Union) is a data structure that tracks elements partitioned into non-overlapping sets. It supports two operations in Read article

⏱ 7 min read String pattern matching — finding a pattern within a larger text — is a fundamental algorithm that powers text editors, Read article

⏱ 6 min read Monotonic stacks and queues are specialized data structures that maintain elements in sorted (increasing or decreasing) order. They solve a Read article

⏱ 6 min read Bit manipulation questions test your understanding of how data is represented at the binary level. These problems appear less frequently Read article

⏱ 8 min read Linked list problems test pointer manipulation skills and appear in approximately 15% of coding interviews. The key to solving them Read article

⏱ 8 min read Backtracking is the go-to technique for problems that require exploring all possible solutions: generating permutations, finding combinations, solving puzzles, and Read article

⏱ 7 min read Hash tables are the most important data structure in computer science — they power dictionaries, sets, caches, database indexes, and Read article

⏱ 7 min read Two pointers and sliding window are among the most powerful techniques for solving array and string problems efficiently. They reduce Read article

⏱ 8 min read Tree problems are the most common category in coding interviews, appearing in approximately 25% of questions at top tech companies. Read article

⏱ 8 min read Concurrency questions test your understanding of parallel execution, synchronization, and the subtle bugs that arise when multiple threads share state. Read article