Topic 04 — Sliding Window
Finished Tue, Aug 25, 2026, 3:01 PM ET: all 4 core problems closed, 3 problems closed that day.
Scheduled: Tue Aug 25, 2026 · Phase: Phase I — Linear Structures · Topic: #6 · Builds on: Topic 3
Closed Aug 25 — the day the topic finished
| Issue | Problem | Set | Difficulty | Closed (ET) | Solution |
|---|---|---|---|---|---|
| #51 | LC 3 · Longest Substring Without Repeating Characters | core | medium | Aug 25 | py · docs |
| #52 | LC 424 · Longest Repeating Character Replacement | core | medium | Aug 25 | py · docs |
| #53 | LC 567 · Permutation in String | core | medium | Aug 25 | py · docs |
Closed earlier
| Issue | Problem | Set | Difficulty | Closed (ET) | Solution |
|---|---|---|---|---|---|
| #50 | LC 121 · Best Time to Buy and Sell Stock | core | easy | Aug 24 | py · docs |
Open at release
| Issue | Problem | Set | Difficulty | Closed (ET) | Solution |
|---|---|---|---|---|---|
| #54 | LC 209 · Minimum Size Subarray Sum | optional | medium | — | — |
| #55 | LC 643 · Maximum Average Subarray | optional | easy | — | — |
| #56 | LC 1004 · Max Consecutive Ones III | optional | medium | — | — |
| #57 | LC 76 · Minimum Window Substring | deferred | hard | — | — |
20260825.190101.000000000 is timever for the UTC instant the core set completed; it tags aba3d9b, the last main commit before it.