LeetCode Spaced Repetition Chrome Extension

A Chrome extension that tracks your LeetCode problem practice using spaced repetition with confidence-based scheduling.

Features

• Manual Confidence Rating: Log your confidence level (1-5) for each problem after solving it
• Smart Scheduling: Dynamic spaced repetition algorithm that prioritizes harder problems
• Daily Review List: See which problems are due for review today
• Max Problems Per Day: Set a limit on daily problems to avoid overload
• Badge Counter: Extension badge shows count of problems due today
• Progress Tracking: View all attempted problems with statistics and average confidence
• Automatic Redistribution: Problems are automatically rescheduled based on priority after each rating

Installation

1. Clone or download this repository
2. Open Chrome and navigate to chrome://extensions/
3. Enable "Developer mode" (toggle in the top right)
4. Click "Load unpacked"
5. Select the extension directory

Usage

Logging Confidence

1. Navigate to any LeetCode problem page (e.g., https://leetcode.com/problems/two-sum/)
2. Solve the problem
3. Open the extension popup
4. Go to the Log tab
5. Select your confidence level:
   • 1 - Very Hard: Struggled significantly
   • 2 - Hard: Found it challenging
   • 3 - Medium: Moderate difficulty
   • 4 - Easy: Solved with ease
   • 5 - Very Easy: Mastered it
6. Click "Log Confidence Rating"

Viewing Your Schedule

• Today Tab: Shows problems due for review today
• All Problems Tab: View all tracked problems sorted by due date
• Settings Tab: Configure max problems per day

Settings

• Max Problems Per Day: Set the maximum number of problems that can be due on any single day
  • When you change this setting, all problems are automatically redistributed
  • Hard problems are prioritized and scheduled before easy ones

How Spaced Repetition Works

The extension uses a confidence-based spaced repetition algorithm:

• Very Easy (5): Scheduled 7 days first time, then 30+ days
• Easy (4): Scheduled 3 days first time, then 14+ days
• Medium (3): Scheduled 1 day first time, then 7 days
• Hard (2): Always scheduled for 1-2 days
• Very Hard (1): Always scheduled for 1 day

Dynamic Scheduling

After each rating, all problems are recalculated and redistributed:

• Hard problems are prioritized and scheduled before easy ones
• Problems are distributed across days respecting your max per day limit
• Historical performance is considered (consistently hard problems stay high priority)
• Problems are never scheduled for the same day they're logged (minimum 1 day)

Technical Details

• Content Script (src/content.js): Detects current LeetCode problem from URL
• Background Service Worker (src/background.js): Manages data storage, spaced repetition calculations, and badge updates
• Popup UI (src/popup.html, src/popup.js): Displays problems, confidence rating interface, and settings
• Storage: Uses Chrome's local storage API to persist problem data locally
• Badge: Shows count of problems due today on extension icon

Project Structure

leetcode-spaced-repetiton-extension/
├── src/                    # Source files
│   ├── background.js       # Service worker
│   ├── content.js          # Content script
│   ├── popup.html         # Popup UI
│   └── popup.js           # Popup logic
├── assets/                 # Icons and images
│   ├── icon16.png
│   ├── icon48.png
│   ├── icon128.png
│   └── logo.svg
├── manifest.json          # Extension manifest
├── README.md              # Documentation
└── LICENSE                # MIT License

Privacy

All data is stored locally in your browser. No data is sent to external servers.

License

MIT License