> For the complete documentation index, see [llms.txt](https://nishchalnishant.gitbook.io/coding/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nishchalnishant.gitbook.io/coding/start-here/readme.md).

# Overview

Topic-first prep for **Google L3** coding loops: 4–5 rounds, one medium problem each, 35–45 minutes. Dense notes, curated must-solve lists, no 500-problem grind.

> **Segment trees & Fenwick trees are not L3 material** — do not drill them. Use prefix sum, deque, or heap instead. Details: [What to Skip at L3](/coding/start-here/l3_cheatsheet.md)

***

## Start here

| Step | Link                                                                                                                                    |
| ---- | --------------------------------------------------------------------------------------------------------------------------------------- |
| 1    | [`coding/l3-google-roadmap.md`](/coding/start-here/l3-google-roadmap.md) — 4-week schedule                                              |
| —    | [**L3 Cheatsheet**](/coding/start-here/l3_cheatsheet.md) — pacing, constraints, decision guide, what to skip                            |
| 2    | [`01-data-structures/README.md`](/coding/data-structures/01-data-structures.md) — DS index + 27 must-solve                              |
| 3    | [`02-algorithms/README.md`](/coding/algorithms/02-algorithms.md) — algo index + 27 must-solve                                           |
| 4    | [`00-L3-EXECUTION-META/L3_CHEATSHEET.md`](/coding/start-here/l3_cheatsheet.md) — pacing, constraints, Python syntax                     |
| 5    | [`coding/`](https://github.com/nishchalnishant/Coding/tree/google-l3-focused/coding/README.md) — problem walkthroughs                   |
| 6    | [`04-behavioral/BEHAVIORAL_GOOGLINESS.md`](/coding/behavioral-required-at-l3/behavioral_googliness.md) — STAR stories, attributes, prep |

***

## What this repo covers (L3)

**Data structures:** array, hashing, string, stack, queue, linked list, tree, trie, heap, graph

**Algorithms:** two pointers, sliding window, binary search, sorting (reference), graphs, union-find, greedy, backtracking, core DP, recursion

**Not in scope for L3:** system design, LLD, concurrency, SQL, **segment trees / Fenwick trees**, advanced graphs (Floyd/Tarjan), bit manipulation deep-dives, bitmask/digit/interval DP — see [What to Skip at L3](/coding/start-here/l3_cheatsheet.md)

***

## Quick revision

| What                                                        | Link                                                                                                     |
| ----------------------------------------------------------- | -------------------------------------------------------------------------------------------------------- |
| Mind map                                                    | [`MINDMAP.md`](/coding/start-here/mindmap.md)                                                            |
| Flowcharts                                                  | [`FLOWCHARTS.md`](/coding/start-here/flowcharts.md)                                                      |
| Pattern triggers                                            | [`03-patterns/patterns-master.md`](/coding/patterns-and-revision/patterns-master.md)                     |
| Full problem index (125, by topic)                          | [`questions.md`](/coding/start-here/questions.md)                                                        |
| **L3 Cheatsheet** (pacing, Big-O, edge cases, what to skip) | [`00-L3-EXECUTION-META/L3_CHEATSHEET.md`](/coding/start-here/l3_cheatsheet.md)                           |
| Interview strategy / day-of revision                        | [`03-patterns/GOOGLE_INTERVIEW_REVISION.md`](/coding/patterns-and-revision/google_interview_revision.md) |

***

## 4-week overview

| Week  | Focus                                                               |
| ----- | ------------------------------------------------------------------- |
| **1** | Arrays, hashing, graphs (BFS/DFS), two pointers, sliding window     |
| **2** | Heaps, tries, queues, binary search (incl. search on answer)        |
| **3** | Trees, stacks, linked lists, union-find, greedy                     |
| **4** | Core DP, backtracking, recursion + **4–6 timed mocks** + behavioral |

Full daily plan: [`coding/l3-google-roadmap.md`](/coding/start-here/l3-google-roadmap.md)