LeetCode Calendar for CoreInk

This project displays your daily LeetCode submission activity on an e-ink screen using the M5Stack CoreInk.

Introduction

This project targets the M5Stack CoreInk. I enjoy tracking my progress — it’s motivating to see the work accumulate over time. That led me to build a small desktop dashboard to visualize my LeetCode activity. Since LeetCode submission data doesn't change frequently, updating a few times per day is enough. The low‑power, always‑visible nature of an e‑ink display makes it a great fit for passive tracking.

Current features include:

1. Automatically fetch recent submission records from LeetCode (CN site) — no account login required.
2. Smart scheduling: active during the day, sleeps at night (sleeps until 10:00).
3. Intelligent updates: refresh only when new submissions are detected.
4. Low power consumption via optimized Wi‑Fi usage.

Screenshot

Setup Instructions

1) Configuration

Before compiling, you need to create a configuration file:

1. Copy src/config.h.example to src/config.h.
2. Edit src/config.h with your settings:

   #define WIFI_SSID "Your_WiFi_SSID"
   #define WIFI_PASSWORD "Your_WiFi_Password"
   #define USERNAME "your-leetcode-username"
   // Optional: timezone and NTP servers
   #define NTP_TIMEZONE "JST-9"
   #define NTP_SERVER1 "ntp.nict.jp"
   #define NTP_SERVER2 "ntp.aliyun.com"
   #define NTP_SERVER3 "ntp1.aliyun.com"

2) Build and Upload

Use PlatformIO to compile and upload the code to your M5Stack CoreInk.

Libraries and References

1. m5stack/M5GFX
2. m5stack/M5Unified
3. m5stack/M5Core-Ink (conflicts with M5Unified)
4. bblanchon/ArduinoJson
5. 如何在不登录的情况下获取LeetCode-CN用户提交记录

Installation and Usage

Use PlatformIO for this project.

1. Create a new project in PlatformIO.

2. Add the following libraries:

   • m5stack/M5GFX@^0.2.6
   • m5stack/M5Unified@^0.2.5
   • bblanchon/ArduinoJson@^7.3.1

3. Copy the code from src/main.cpp into your project (this repo uses a single editable file) and edit src/config.h.

4. Build and upload to your CoreInk.

FAQ

Q:

How do I configure my own settings?

A:

// Edit src/config.h
#define WIFI_SSID "******"
#define WIFI_PASSWORD "******"
#define USERNAME "******" // Your LeetCode username

If necessary, handle any concerns around storing plaintext passwords yourself.

Changelog

• 0.2.0 (Jul 15, 2025): Handled timeouts for LeetCode API requests.
• 0.1.0 (Apr 05, 2025): Initial release.

License

MIT License.

Contact

Questions or feedback are welcome: Shou Qiu [email protected].