Week 02 — May 18–24, 2026 — Linked List
Week 02 (May 18 – May 24, 2026) — LINKED LIST
15 problems (NeetCode 11 + 4 extended). Timer on, solo, no hints until timer expires. Carry-over: STAR drills + pre-screen Q drafts from W1. SD theory: 4 sections (Caching + Async + Resiliency + Essentials). Decision gate Sun May 24.
→ Full curriculum: [[Coach/project_dsa_sd_curriculum]] → Coach state: [[synthesis/Coach Hub]]
Goals This Week
- Theory block — [[DSA/DSA Techniques for Interviews/06. Linked Lists]] + NeetCode Linked List intro ✅ May 18
- 15 DSA problems on time, solo — timer rules same as W1 ✅ 2026-05-25
- SD theory: Caching + Asynchronous Systems + Resiliency + Essentials (4 sections, ~9h)
- BA drills: WebSocket geo STAR (10 reps) + AskTGE STAR (5 reps)
- Drill Qs: "Why leaving HCL?" + "Expected CTC?" + "2-min intro" — drafted + rehearsed fluently
- Sun May 24 scorecard completed + W3 direction set
DSA Problem Set (15)
Rules: timer on, no editorial/AI/peek until timer expires. One sitting per problem. Mark fail if timer expires.
| # | Pattern | Problem | LC | Diff | Target | Solved? | Time | Bugs / notes |
|---|---|---|---|---|---|---|---|---|
| 1 | Linked List | Reverse Linked List | 206 | E | 10 min | Yes | 3:43 | |
| 2 | Linked List | Merge Two Sorted Lists | 21 | E | 15 min | Yes | 4:42 | |
| 3 | Linked List | Linked List Cycle | 141 | E | 10 min | Yes | 1:30 | |
| 4 | Linked List | Middle of the Linked List | 876 | E | 10 min | Yes | 2:00 | |
| 5 | Linked List | Reorder List | 143 | M | 30 min | Yes | 20:00 | |
| 6 | Linked List | Remove Nth Node from End | 19 | M | 25 min | Yes | 20:00 | |
| 7 | Linked List | Copy List with Random Pointer | 138 | M | 30 min | Yes | 20:00 | Tail not restored — C.next still → C' after separation |
| 8 | Linked List | Add Two Numbers | 2 | M | 25 min | Yes | 15:00 | quo = remainder not quotient — name it digit |
| 9 | Linked List | Reverse Linked List II | 92 | M | 25 min | Yes | 20:00 | |
| 10 | Linked List | Palindrome Linked List | 234 | M | 25 min | Yes | 20:00 | |
| 11 | Linked List | Odd Even Linked List | 328 | M | 25 min | FAIL | 34:00 | TIMER BLOWN (34/25 min). Rotation insert approach instead of two-chain + rejoin |
| 12 | Linked List | Find the Duplicate Number | 287 | M | 35 min | Yes | 24:00 | Phase 2 non-canonical — predecessor check instead of standard Floyd's reset-to-0 |
| 13 | Linked List | LRU Cache | 146 | M | 40 min | Yes | 36:00 | Initial typo self.head=None in Node (caught + fixed). Canonical DLL+hashmap. |
| 14 | Linked List | Merge K Sorted Lists | 23 | H | 45 min | Yes* | 15:00 | heapq explained mid-session — not cold. Pattern absorbed in 1 rep. Asterisked. |
| 15 | Linked List | Reverse Nodes in K-Group | 25 | H | 50 min | Yes | 43:00 | Insertion-at-front + undo block — works but non-canonical. Canonical = getKth first, then standard reversal, no undo needed. |
Score: 13/15 solved on time (1 FAIL — 328 timer blown; 1 asterisked — 23 heapq taught mid-session)
SD Theory Tracker
| Section | Status | Notes |
|---|---|---|
| Caching (4 topics) | Done | All Things Caching / Understanding / Populating & Scaling / Architecture levels |
| Asynchronous Systems (4 topics) | ⬜ | Async Processing / Message Queues / Kafka Essentials / Real-time PubSub |
| Resiliency (5 topics) | ⬜ | Designing for Resiliency / Load Balancers / Circuit Breakers / Data Redundancy / Leader Election |
| Essentials (5 topics) | ⬜ | Bloom Filters / Consistent Hashing / Client-server & Protocols / Blob Storage & S3 / Intro to Big Data |
BA Drills Tracker
| Story | Reps done | Target | Notes |
|---|---|---|---|
| WebSocket Geo (TGE Logistics) | 3 | 10 reps | 250+ drivers, sub-second, hybrid hydration |
| AskTGE (DynamoDB + perf audit) | 1 | 5 reps | 90% token cost ↓, 50× bandwidth ↓, 2s→200ms |
Drill Questions Tracker
| Question | Drafted? | Rehearsed? |
|---|---|---|
| "Why are you leaving HCL?" | Done | ⬜ |
| "What's your expected CTC?" | Done | ⬜ |
| "Walk me through your background (2 min)" | Done | ⬜ |
Daily Plan
Mon May 18
- Theory block: Read [[DSA/DSA Techniques for Interviews/06. Linked Lists]] + NeetCode Linked List intro (1.5h) ✅
Tue May 19
- LC 206, 21, 141, 876 (4 easies, ~45 min + review) ✅ 2026-05-21
- SD theory: Caching pt 1 (~1h) ✅ 2026-05-25
- BA: WebSocket geo STAR (3 reps) ✅ 2026-05-25
- Target: 2.5h
Wed May 20
- LC 143, 19 (2 mediums, ~55 min + review) ✅ 2026-05-25
- SD theory: Caching pt 2 (~1h) ✅ 2026-05-25
- BA: WebSocket geo STAR (4 reps) ✅ 2026-05-25
- Target: 3h
Thu May 21
- LC 138, 2, 92 (3 mediums, ~1.5h + review) ✅ 2026-05-25
- SD theory: Async Systems pt 1 (~1h) ✅ 2026-05-25
- BA: AskTGE STAR (3 reps) + Drill Q: "Why leaving HCL?" draft
- Target: 3h
Fri May 22
- LC 234, 328 (2 mediums, ~50 min + review) ✅ 2026-05-25
- Drill Qs: "Expected CTC?" + "2-min intro" draft ✅ 2026-05-25
- Target: 2.5h
Sat May 23 — Heavy day
- LC 287, 146 (2 mediums, ~1.25h + review) ✅ 2026-05-25
- LC 23, 25 (2 hards, ~1.5h + review) ✅ 2026-05-25
- SD theory: Async Systems pt 2 + Resiliency (~3h)
- Drill Qs: polish all 3 answers
- Target: 7h
Sun May 24 — Retro day
- SD theory: Essentials (~2.5h)
- Pre-screen Qs final rehearsal (1h)
- Write scorecard + W3 direction (run
/coach scorecard) - Target: 7h
Decision Gate (Sun May 24)
| Score on time | Verdict | W3 plan |
|---|---|---|
| 13–15 | Pass — strong | Trees pt 1 (all NeetCode Trees problems) |
| 10–12 | Pass — patchy | Trees pt 1 + 2 retry from weakest LL problems |
| < 10 | Fail | Repeat Linked List in W3, Trees → W4 |
Hours Log
| Day | Planned | Actual | What blocked? |
|---|---|---|---|
| Mon | 1.5h | 1.5h | — |
| Tue | 2.5h | ||
| Wed | 3h | ||
| Thu | 3h | ||
| Fri | 2.5h | ||
| Sat | 7h | ||
| Sun | 7h | ||
| Total | 27h |
Week Retro (filled 2026-05-25)
Scorecard
- Problems solved on time: 13/15 (1 FAIL — LC 328 timer blown; 1 asterisked — LC 23 heapq taught mid-session)
- Total time: ~277 min vs 400 min target (used 69% of allocated time)
- Weakest pattern: Odd Even LL (328) — defaulted to rotation-insert instead of two-chain rejoin. K-Group (25) — non-canonical undo block instead of getKth first.
- Strongest pattern: Easies (all under 5 min), Floyd's cycle (287 in 24/35 min), LRU Cache (36/40 min, canonical on second attempt)
SD theory completed
- Sections done: 1/4 (Caching ✅ — Async + Resiliency + Essentials → carry W3)
BA + Drill Qs
- WebSocket geo reps: 3/10
- AskTGE reps: 1/5
- Drill Qs drafted + rehearsed: 3/3 drafted, 0/3 rehearsed → 0/3 complete
What slipped
SD theory got cut every day DSA ran long — no protected time block. BA drills had no fixed slot. Both treated as "fill remaining time" tasks, which meant they never happened when DSA + work ate the day.
What surprised me
External interruptions not present in W1: friend visit on Sunday wiped retro day, heavy weekday work load cut available hours. W1 was cleaner — W2 revealed that the schedule has no buffer for life events.
W3 decision
PASS STRONG → Trees pt 1 (May 25–31)
One thing to fix in W3
Protect non-DSA time with fixed slots — schedule SD theory and Drill Qs rehearsal as immovable blocks, not "after DSA is done."