Topic 01 — Hash-Based Lookup
Finished Mon, Aug 24, 2026, 2:20 PM ET: all 5 core problems closed, 5 problems closed that day.
Scheduled: Mon Aug 17, 2026 · Phase: Phase I — Linear Structures · Topic: #3 · Builds on: nothing
Closed Aug 24 — the day the topic finished
| Issue | Problem | Set | Difficulty | Closed (ET) | Solution |
|---|---|---|---|---|---|
| #27 | LC 217 · Contains Duplicate | core | easy | Aug 24 | js · docs |
| #28 | LC 242 · Valid Anagram | core | easy | Aug 24 | js · docs |
| #29 | LC 1 · Two Sum | core | easy | Aug 24 | — |
| #30 | LC 49 · Group Anagrams | core | medium | Aug 24 | js · docs |
| #31 | LC 347 · Top K Frequent Elements | core | medium | Aug 24 | js · docs |
Open at release
| Issue | Problem | Set | Difficulty | Closed (ET) | Solution |
|---|---|---|---|---|---|
| #32 | LC 383 · Ransom Note | optional | easy | — | — |
| #33 | LC 205 · Isomorphic Strings | optional | easy | — | — |
| #34 | LC 128 · Longest Consecutive Sequence | optional | medium | — | — |
| #35 | LC 290 · Word Pattern | optional | easy | — | — |
20260824.182006.000000000 is timever for the UTC instant the core set completed; it tags 32a41bd, the last main commit before it.