# suryav2006-git/leetcode-practice-solutions architecture

> Architecture diagram of the GitHub repository suryav2006-git/leetcode-practice-solutions, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-08-14). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/suryav2006-git/leetcode-practice-solutions
- Repository: https://github.com/suryav2006-git/leetcode-practice-solutions

## Overview

#### Purpose and Shape
This is a LeetCode solution corpus, not a deployable application. Each numbered directory is an independent problem unit containing a problem README and one or more language-specific submissions. The root catalog groups problems by algorithmic topic; `stats.json` is repository-level metadata.

#### Entry Points and Execution Boundary
There is no shared executable, package manifest, service, or application runtime. The effective entry points are LeetCode-compatible solution files, invoked by the LeetCode judge with platform-provided inputs and types:
- `0001-two-sum/0001-two-sum.cpp`
- `0001-two-sum/0001-two-sum.java`
- `0001-two-sum/0001-two-sum.py`

Each file must be compiled/interpreted independently in its selected language; solutions are not intended to call one another.

#### Problem-Unit Contract
A directory is the primary architectural boundary: problem statement/documentation plus alternative implementations of the same contract. Language coverage varies by problem.
- `0002-add-two-numbers/README.md`
- `0002-add-two-numbers/0002-add-two-numbers.cpp`
- `0002-add-two-numbers/0002-add-two-numbers.java`

Inputs, outputs, and judge-owned structures such as linked-list or tree nodes are externalized to LeetCode. Local code provides the expected algorithm method/class rather than CLI parsing, persistence, or network handling.

#### Algorithm Families: Sequence and Search
A large portion addresses arrays using hashing, sorting, pointers, sliding windows, and binary-search variants. These are isolated implementations rather than reusable shared modules.
- `0015-3sum/0015-3sum.cpp`
- `0033-search-in-rotated-sorted-array/0033-search-in-rotated-sorted-array.java`
- `1011-capacity-to-ship-packages-within-d-days/1011-capacity-to-ship-packages-within-d-days.cpp`

Typical flow: judge supplies an array/string and parameters → solution derives an answer or mutates the supplied collection → judge validates result.

#### Algorithm Families: Structured Data and Traversal
Linked-list, tree, and grid problems rely on judge-provided node/grid models. Traversal or pointer-rewiring remains contained within the corresponding problem directory.
- `0206-reverse-linked-list/0206-reverse-linked-list.py`
- `0098-validate-binary-search-tree/0098-validate-binary-search-tree.cpp`
- `0200-number-of-islands/0200-number-of-islands.java`

Important boundary: list/tree node declarations and test harnesses are not repository-owned; code must remain compatible with platform definitions.

#### Multi-Runtime Support
The material runtimes are C, C++, Java, Python, and SQL, with C++ and Java present for most units. SQL is used for the database-specific challenge:
- `0007-reverse-integer/0007-reverse-integer.c`
- `0509-fibonacci-number/0509-fibonacci-number.py`
- `0175-combine-two-tables/0175-combine-two-tables.sql`

There are no declared external services, databases, APIs, deployment infrastructure, or cross-language build orchestration. The only external execution environment is LeetCode’s online judge and, for SQL, its supplied relational schema/data.

#### Repository-Level Index
The root README acts as a topic-to-directory navigation index, while each leaf README describes its individual challenge.
- `README.md`
- `stats.json`
- `0875-koko-eating-bananas/README.md`

Adding a solution means creating/updating an independent numbered directory and its implementations; it does not require modifying a central runtime or dependency graph.

Main entry points: [`0002-add-two-numbers/README.md`](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0002-add-two-numbers/README.md) (Problem Statement), [`README.md`](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/README.md) (Topic Catalog), [`0206-reverse-linked-list/0206-reverse-linked-list.py`](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0206-reverse-linked-list/0206-reverse-linked-list.py) (Structured Traversal Solutions), [`0015-3sum/0015-3sum.cpp`](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0015-3sum/0015-3sum.cpp) (Sequence & Search Solutions)

## Diagram (Mermaid)

```mermaid
flowchart TD

subgraph group_repo["Repository Index"]
  node_root_readme["Topic Catalog<br/>Markdown index<br/>[README.md]"]
  node_stats["Repository Stats<br/>JSON metadata<br/>[stats.json]"]
end

subgraph group_units["Independent Problem Units"]
  node_problem_readme["Problem Statement<br/>Challenge README<br/>[README.md]"]
  node_two_sum_cpp["Two Sum C++<br/>C++ submission<br/>[0001-two-sum.cpp]"]
  node_two_sum_java["Two Sum Java<br/>Java submission<br/>[0001-two-sum.java]"]
  node_two_sum_python["Two Sum Python<br/>Python submission<br/>[0001-two-sum.py]"]
  node_sequence_search["Sequence &amp; Search Solutions<br/>Isolated algorithms<br/>[0015-3sum.cpp]"]
  node_structured_traversal["Structured Traversal Solutions<br/>Isolated algorithms"]
  node_sql_solution["SQL Challenge<br/>SQL submission"]
  node_leaf_readme["Leaf Challenge Docs<br/>Challenge README<br/>[README.md]"]
end

subgraph group_platform["LeetCode Platform"]
  node_native_runtimes{{"C / C++ Runtimes<br/>Independent compilation"}}
  node_managed_runtimes{{"Java / Python Runtimes<br/>Independent execution"}}
  node_judge{{"Online Judge<br/>External platform"}}
  node_judge_models[("Provided Models &amp; Schema<br/>External contracts")]
end

node_root_readme -->|"indexes"| node_problem_readme
node_root_readme -->|"navigates to"| node_sequence_search
node_root_readme -->|"navigates to"| node_structured_traversal
node_stats -.->|"summarizes corpus"| node_root_readme
node_problem_readme -->|"defines contract"| node_two_sum_cpp
node_problem_readme -->|"defines contract"| node_two_sum_java
node_problem_readme -->|"defines contract"| node_two_sum_python
node_two_sum_cpp -->|"compiled independently"| node_native_runtimes
node_two_sum_java -->|"executed independently"| node_managed_runtimes
node_two_sum_python -->|"executed independently"| node_managed_runtimes
node_sequence_search -->|"submitted to"| node_judge
node_structured_traversal -->|"uses provided types"| node_judge_models
node_structured_traversal -->|"submitted to"| node_judge
node_sql_solution -->|"queries supplied schema"| node_judge_models
node_sql_solution -->|"executed by"| node_judge
node_native_runtimes -->|"hosted by"| node_judge
node_managed_runtimes -->|"hosted by"| node_judge
node_leaf_readme -.->|"documents a unit"| node_sequence_search

click node_root_readme "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/README.md"
click node_stats "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/stats.json"
click node_problem_readme "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0002-add-two-numbers/README.md"
click node_two_sum_cpp "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.cpp"
click node_two_sum_java "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.java"
click node_two_sum_python "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.py"
click node_sequence_search "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0015-3sum/0015-3sum.cpp"
click node_structured_traversal "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0206-reverse-linked-list/0206-reverse-linked-list.py"
click node_sql_solution "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0175-combine-two-tables/0175-combine-two-tables.sql"
click node_leaf_readme "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0875-koko-eating-bananas/README.md"
click node_native_runtimes "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0007-reverse-integer/0007-reverse-integer.c"
click node_managed_runtimes "https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0509-fibonacci-number/0509-fibonacci-number.py"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_root_readme,node_stats toneBlue
class node_problem_readme,node_two_sum_cpp,node_two_sum_java,node_two_sum_python,node_sequence_search,node_structured_traversal,node_sql_solution,node_leaf_readme toneAmber
class node_native_runtimes,node_managed_runtimes,node_judge,node_judge_models toneMint
```

## Components

### Repository Index

- [Topic Catalog](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/README.md): Markdown index · Maps algorithm topics to problem directories. · `README.md`
- [Repository Stats](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/stats.json): JSON metadata · `stats.json`

### Independent Problem Units

Each directory is an isolated LeetCode contract.

- [Problem Statement](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0002-add-two-numbers/README.md): Challenge README · Documents an individual challenge contract. · `0002-add-two-numbers/README.md`
- [Two Sum C++](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.cpp): C++ submission · `0001-two-sum/0001-two-sum.cpp`
- [Two Sum Java](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.java): Java submission · `0001-two-sum/0001-two-sum.java`
- [Two Sum Python](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0001-two-sum/0001-two-sum.py): Python submission · `0001-two-sum/0001-two-sum.py`
- [Sequence & Search Solutions](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0015-3sum/0015-3sum.cpp): Isolated algorithms · Hashing, sorting, pointers, windows, and binary search variants. · `0015-3sum/0015-3sum.cpp`
- [Structured Traversal Solutions](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0206-reverse-linked-list/0206-reverse-linked-list.py): Isolated algorithms · List, tree, and grid traversal or rewiring. · `0206-reverse-linked-list/0206-reverse-linked-list.py`
- [SQL Challenge](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0175-combine-two-tables/0175-combine-two-tables.sql): SQL submission · Runs against a judge-supplied relational schema. · `0175-combine-two-tables/0175-combine-two-tables.sql`
- [Leaf Challenge Docs](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0875-koko-eating-bananas/README.md): Challenge README · `0875-koko-eating-bananas/README.md`

### LeetCode Platform

Judge-owned execution environment and types.

- [C / C++ Runtimes](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0007-reverse-integer/0007-reverse-integer.c): Independent compilation · `0007-reverse-integer/0007-reverse-integer.c`
- [Java / Python Runtimes](https://github.com/suryav2006-git/leetcode-practice-solutions/blob/main/0509-fibonacci-number/0509-fibonacci-number.py): Independent execution · `0509-fibonacci-number/0509-fibonacci-number.py`
- **Online Judge**: External platform · Supplies inputs, validates outputs, and invokes each submission independently.
- **Provided Models & Schema**: External contracts · Provides node types, grids, harnesses, and SQL data.

## Connections

- Topic Catalog → Problem Statement: indexes
- Topic Catalog → Sequence & Search Solutions: navigates to
- Topic Catalog → Structured Traversal Solutions: navigates to
- Repository Stats → Topic Catalog: summarizes corpus
- Problem Statement → Two Sum C++: defines contract
- Problem Statement → Two Sum Java: defines contract
- Problem Statement → Two Sum Python: defines contract
- Two Sum C++ → C / C++ Runtimes: compiled independently
- Two Sum Java → Java / Python Runtimes: executed independently
- Two Sum Python → Java / Python Runtimes: executed independently
- Sequence & Search Solutions → Online Judge: submitted to
- Structured Traversal Solutions → Provided Models & Schema: uses provided types
- Structured Traversal Solutions → Online Judge: submitted to
- SQL Challenge → Provided Models & Schema: queries supplied schema
- SQL Challenge → Online Judge: executed by
- C / C++ Runtimes → Online Judge: hosted by
- Java / Python Runtimes → Online Judge: hosted by
- Leaf Challenge Docs → Sequence & Search Solutions: documents a unit