LC 94
Binary Tree Inorder Traversal
Easy · LC 1–100 + first-family candidate
Candidate solution routes
Primary
FreeTree recursive aggregation
Invariant: dfs(u) returns a summary concerning only u's subtree and satisfying its parent contract; before return, every global candidate fully contained in that subtree has been considered.
candidate confidence: 0.665 · metadata_only
Alternate 1
FreeDFS Components and Reachability
Invariant: Once marked visited, a vertex belongs to the component represented by the current search and can never join a later component.
candidate confidence: 0.610 · metadata_only
How to use this page
Read the statement and constraints first, then validate recognition signals, invariant, and complexity. Candidate score is not correctness evidence.