Week 08 (Jul 13 – Jul 19, 2026) — ADVANCED GRAPHS + GREEDY (Sprint S4 of 8)
14 problems. Timer on, solo, no peek till timer expires.
→ Curriculum: [[Coach/project_dsa_sd_curriculum]] | Coach state: [[synthesis/Coach Hub]]
Goals This Week
DSA Problem Set (14)
| # | Problem | LC | Diff | Target | Solved? | Time | Notes |
|---|
| 1 | Network Delay Time | 743 | M | 30 min | ☐ | | Dijkstra |
| 2 | Min Cost to Connect Points | 1584 | M | 30 min | ☐ | | Prim's MST |
| 3 | Cheapest Flights Within K Stops | 787 | M | 35 min | ☐ | | Bellman-Ford / BFS+k |
| 4 | Reconstruct Itinerary | 332 | H | 35 min | ☐ | | Hierholzer Euler path |
| 5 | Swim in Rising Water | 778 | H | 35 min | ☐ | | Dijkstra / binary search+DFS |
| 6 | Alien Dictionary | 269 | H | 40 min | ☐ | | topo sort on chars |
| 7 | Maximum Subarray | 53 | M | 15 min | ☐ | | Kadane |
| 8 | Jump Game | 55 | M | 20 min | ☐ | | greedy reach |
| 9 | Jump Game II | 45 | M | 25 min | ☐ | | BFS-levels greedy |
| 10 | Gas Station | 134 | M | 25 min | ☐ | | total>=0 + reset start |
| 11 | Hand of Straights | 846 | M | 25 min | ☐ | | count map + min-heap |
| 12 | Merge Triplets to Form Target | 1899 | M | 25 min | ☐ | | filter then OR-merge |
| 13 | Partition Labels | 763 | M | 25 min | ☐ | | last-index greedy |
| 14 | Valid Parenthesis String | 678 | M | 25 min | ☐ | | low/high open count |
Score: __/14 on time
SD + Redis + DDIA
| Item | Status | Notes |
|---|
| SD: WhatsApp / Chat | ⬜ | online presence, delivery receipts, message fan-out, WebSocket |
| Redis: pub/sub + streams | ⬜ | PUBLISH/SUBSCRIBE, XADD/XREAD consumer groups |
| DDIA: Ch7 Sharding pt2 | ⬜ | rebalancing, request routing |
Daily Plan (compact)
- Mon: Dijkstra/MST refresh + LC 743, 1584
- Tue: LC 787, 332
- Wed: LC 778, 269 + Redis pub/sub
- Thu: LC 53, 55, 45 + SD Chat high-level
- Fri: LC 134, 846, 1899 + DDIA Ch7.2
- Sat: LC 763, 678 + Chat whiteboard
- Sun: retro + scorecard + create S5 tracker
Decision Gate (Sun Jul 19)
| Score | Verdict | S5 |
|---|
| 11–14 | Pass strong | 1-D DP (12) + Uber/Yelp + Redis GEO |
| 8–10 | Patchy | 1-D DP + retry weak |
| <8 | Fail | Patch graphs/greedy in S5 |
Hours Log
| Day | Planned | Actual |
|---|
| Mon–Sun | ~26h | |
Retro (fill Sun)
- Solved on time: __/14 | Weakest: __ | SD: __ | Redis: __ | DDIA: __ | S5 decision: __