Month 1 — Foundations
Weeks 1–4 · 20 flagship problems · ~115 LC Bank problems · 1 mock
Goals
By end of month, you can:
- Execute the 16-step framework on every problem without thinking about it
- Solve any LC Easy in <12 min with full edge-case coverage
- Solve straightforward Mediums (array/string/hashmap/tree/basic-DP) in <30 min
- Explain hashmap collision handling, GC, stack vs heap in your primary language
- Pass mock-02 (Easy) at 7+/10
Weekly Map
| Week | Theme | Flagship Problems | Phase Reading |
|---|---|---|---|
| 1 | Execution baseline + first patterns | p01–p05 | phase-00, phase-01 §1–3 |
| 2 | Arrays + strings + hashmaps deep | p06–p10 | phase-01 §1–3 runtime, phase-09 your lang first half |
| 3 | Heaps, binary search, trees | p11–p15 | phase-01 §4–7 |
| 4 | LRU, DFS/BFS, DP intro, backtracking intro | p16–p20 | phase-01 §8–9, phase-09 second half |
End-of-Month Gate
- All 20 flagship problems: Section 9 (“When to Move On”) checklist green
- All Phase 1 mastery checks in phase-01-foundations/README.md pass
- mock-02 scored 7+/10
- Tracking spreadsheet has 20 entries with Level Delta self-assessment
If any item fails: do NOT enter Month 2. Repeat the weakest week’s drilling.
Why These 20 Problems
These are the 20 most-asked Easy-and-low-Medium problems in 2024–2025 Big Tech interview loops (cross-referenced against company tag data, real-time interview reports, and recruiter intel). They are the floor. If you cannot solve all 20 fluently, you will fail the phone screen — not because they are hard, but because failing an Easy in 12 minutes is an instant no-hire signal.