2026-02-01 · 10 min read
Complete DFS Guide for Coding Interviews
Depth-first search patterns: trees, graphs, backtracking, and pitfalls.
Complete DFS Guide
DFS is the workhorse for trees, graphs, and backtracking.
Templates
- Recursive tree DFS
- Graph adjacency list DFS with visited set
- Backtracking with choose / explore / unchoose
Practice: Number of Islands, Clone Graph.