LC 26
Remove Duplicates from Sorted Array
Easy · LC 1–100
Candidate solution routes
Primary
FreeSame-Direction / Read-Write Pointers
Invariant: After processing a[0:read], a[0:write] is exactly its correct stable filtered output, with write no farther than read+1.
candidate confidence: 0.599 · metadata_only
Alternate 1
FreeOpposite-Direction Two Pointers
Invariant: Every uneliminated pair uses endpoints inside [l,r]; a moved endpoint is proven unable to pair with any remaining opposite endpoint to satisfy the goal.
candidate confidence: 0.452 · 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.