BFS vs DFS: Choosing the Right Graph Traversal for the Job
Understand the difference between breadth-first and depth-first search, when each traversal is the right fit, and how they show up in trees, graphs, and grids.
graphs
bfs
dfs
traversal
Coding interview patterns & LeetCode walkthroughs
Practical guides to the algorithm patterns that show up in real interviews.
Heap Pattern: When a Priority Queue Beats Sorting Everything
Learn when heaps are the right data structure, how min-heaps and max-heaps work, and why they shine in top-k and streaming problems.
heap
priority-queue
top-k
data-structures
Union-Find Pattern: The Cleanest Way to Track Connected Components
Understand disjoint set union, path compression, and union by rank so you can solve connectivity problems efficiently.
union-find
graphs
connectivity
data-structures
Topological Sort: The Pattern for Dependency Ordering Problems
Learn how topological sorting works, why it only applies to DAGs, and how to solve course scheduling and dependency ordering problems.
topological-sort
graphs
dag
dependencies
Ready to practice these patterns?
Step through interactive lessons — trace variables, visualize the algorithm, and practice until it clicks.
Browse the lessons