Week 06 RESTART — Jul 29–Aug 4, 2026 — Backtracking
Week 06 RESTART (Jul 29 – Aug 4, 2026) — BACKTRACKING
Restart after a 4-week DSA stall (old W06-W10 trackers superseded, archived to
Archive/Superseded Trackers 2026-07-29/). Last verified pattern done: Tries + Heap (W05, Jun 28). This is Day 1 of the new plan. Timer on, solo, no peek till timer expires.
→ Curriculum: [[Coach/project_dsa_sd_curriculum]] | Coach state: [[Interview Prep/Coach Hub]] | Live status: [[Interview Prep/Dashboard]]
Goals This Week
- 9 DSA problems on time, solo
- SD: finish the unread half of Concepts (mark up in [[Interview Prep/System Design/index]])
- SD: Twitter Feed problem design (next after URL Shortener)
- Sun Aug 2 scorecard + Week 2 direction — actually do this retro this time
DSA Problem Set (9)
| # | Problem | LC | Diff | Target | Solved? | Time | Bugs / notes |
|---|---|---|---|---|---|---|---|
| 1 | Subsets | 78 | M | 20 min | ☑ | 3 min | template: choose/explore/un-choose — clean, well under target |
| 2 | Combination Sum | 39 | M | 25 min | ☑ | 10 min | reuse allowed → don't advance idx — clean, well under target |
| 3 | Permutations | 46 | M | 25 min | ☑ | 5 min | used[] vs swap — used num not in perm (O(n) scan), should be used[] array O(1); correct but not clean |
| 4 | Subsets II | 90 | M | 25 min | ☑ | 8 min | sort + skip dup at same level — clean, well under target |
| 5 | Combination Sum II | 40 | M | 30 min | ☑ | 5 min | dup skip + advance idx — clean, well under target |
| 6 | Word Search | 79 | M | 30 min | ☑ | 15 min | grid DFS + visited mark/unmark — clean, well under target (bracket typo was paste artifact, not real) |
| 7 | Palindrome Partitioning | 131 | M | 30 min | ☑ | 20 min | isPalindrome helper + cut points — clean, under target |
| 8 | Letter Combinations of Phone No. | 17 | M | 20 min | ☑ | 9 min | digit→letters map — missed empty-digits edge case (returns [""] not []) |
| 9 | N-Queens | 51 | H | 40 min | ☑ | 36 min | col/diag/anti-diag sets — correct, close to target; had dead-code line (rows = cols = n immediately overwritten) |
Score: 9/9 on time
Decision Gate (Sun Aug 2)
| Score | Verdict | Week 2 |
|---|---|---|
| 7–9 | Pass strong | Graphs (13) |
| 5–6 | Patchy | Graphs + retry weakest backtracking |
| <5 | Fail | Repeat Backtracking |
Retro (fill Sun — do not skip this time)
- Solved on time: __/9 | Weakest: __ | SD Concepts read: __ | SD problem: __ | Restart holding: Y/N