LC Calendar

A CLI tool to track LeetCode problem revisits using spaced repetition.

Installation

uv pip install -e .

Usage

View today's problems

lccal today

Shows problems due today and all past pending problems that haven't been completed.

Add a problem

lccal add <problem_number>              # Add for today
lccal add <problem_number> <date>       # Backfill for past date
lccal add <problem_number> -e           # Extended mode (today)
lccal add <problem_number> <date> -e    # Extended mode (past date)

Records a problem and creates revisit dates. If no date is provided, uses today's date. Date format: MM/DD/YYYY or MM/DD/YY

Standard mode (default):

• Revisit #1: 3 days later
• Revisit #2: 14 days later (2 weeks)
• Revisit #3: 30 days later (1 month)

Extended mode (-e or --extended):

• Revisit #1-3: Same as standard
• Revisit #4: 3 months later
• Revisit #5: 6 months later
• Revisit #6: 1 year later

Examples:

• lccal add 123 - Add problem 123 for today
• lccal add 456 12/20/25 - Backfill problem 456 for 12/20/25
• lccal add 789 -e - Add problem 789 with extended pattern

Mark problem as complete

lccal done <problem_number>

Marks the oldest pending revisit as completed.

Note: if you fail a retry, simply use lccal del <problem_number> then lccal prob <problem_number> to reset and shift the revisit pattern into the future starting from today's date

Delete a problem

lccal del <problem_number>

Removes all revisits for a problem.

View statistics

lccal stats                    # Stats from first recorded day to today
lccal stats <start_date>       # Stats from specified date to today

Displays statistics about your problem-solving habits including:

• Total problems attempted
• Mean, median, standard deviation, range, and mode of problems per day
• Interactive graph showing problems attempted per day over time

Date format: MM/DD/YYYY or MM/DD/YY

The graph and statistics include all days in the range (with 0 values for days without problems).

Examples:

• lccal stats - Show stats from first recorded day to today
• lccal stats 12/01/24 - Show stats from 12/01/24 to today
• lccal stats 12/15/2024 - Show stats from 12/15/2024 to today

Data Storage

Data is stored in ~/.lccal_data.json with the following structure:

{
  "dates": {
    "12/27/2025": [
      {
        "number": 123,
        "revisit": 1,
        "completed": false
      }
    ]
  }
}

Timezone

All dates use CST (America/Chicago) timezone.

Project Structure

The project is organized as a Python package with the following structure:

lc_calendar/
├── __init__.py          # Package exports
├── cli.py               # CLI entry point and argument parsing
├── config.py            # Configuration constants (DATA_FILE, CST_TZ, Colors)
├── storage.py           # Data persistence (load_data, save_data)
├── date_utils.py        # Date manipulation utilities
├── core.py              # Business logic (add_problem_to_dates)
└── commands.py          # Command handlers (cmd_today, cmd_add, cmd_del, cmd_done, cmd_stats)

This modular structure provides:

• Clear separation of concerns: Each module has a specific responsibility
• Easy testing: Individual modules can be tested in isolation
• Maintainability: Changes are localized to relevant modules
• Extensibility: New features can be added without modifying existing code