CTC
Cataloging the Cryptic
Formatting Reference & Tutorial

Markdown Formatting Guide

Learn how to format constraint definitions, puzzle rulesets, author biographies, and app descriptions with bullet points, arrows, coordinates, and emphasis across Cataloging the Cryptic.

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Jump to: 1. Text & Emphasis 2. Bullet & Numbered Lists 3. Arrows & HTML Entities 4. Callout Quotes 5. Coordinates & Code 6. Links & Tables 7. Live Playground
1

Text Formatting, Headings & Emphasis

Use asterisks or underscores for emphasis, and hashtags for hierarchical section titles.

WHAT YOU TYPE (MARKDOWN) 
### Standard Sudoku Rules
Normal **Sudoku** rules apply. Each row, column, and 3x3 box must contain the digits 1 through 9 without *repetition*.

#### Variations
Use ~~strikethrough~~ for deprecated rules, or ***bold-and-italic*** for paramount restrictions.
HOW IT RENDERS IN CTC

Standard Sudoku Rules

Normal Sudoku rules apply. Each row, column, and 3x3 box must contain the digits 1 through 9 without repetition.

Variations

Use strikethrough for deprecated rules, or bold-and-italic for paramount restrictions.

2

Bullet Lists & Numbered Steps

Prefix lines with asterisks (`*`) or hyphens (`-`) for bullet points, and numbers (`1.`, `2.`) for step-by-step rules.

WHAT YOU TYPE (MARKDOWN) 
* **German Whispers:** Adjacent digits along green lines must differ by at least 5.
* **Renban Lines:** Digits along purple lines must be consecutive in any order:
  * No digits may repeat on a Renban line.
* **Kropki Pairs:**
  * White dot: Digits differ by exactly 1.
  * Black dot: Digits are in a 1:2 ratio.

1. First, deduce parity on row 1.
2. Next, disambiguate the center box.
HOW IT RENDERS IN CTC
  • German Whispers: Adjacent digits along green lines must differ by at least 5.
  • Renban Lines: Digits along purple lines must be consecutive in any order:
    • No digits may repeat on a Renban line.
  • Kropki Pairs:
    • White dot: Digits differ by exactly 1.
    • Black dot: Digits are in a 1:2 ratio.
  1. First, deduce parity on row 1.
  2. Next, disambiguate the center box.
3

Arrows & Mathematical Entities

Use standard HTML entities or copy Unicode characters directly into your text.

WHAT YOU TYPE (MARKDOWN / ENTITIES) 
* **Arrow Sums:** Digits along the arrow sum to the bulb:
  * Cell A → Cell B → Bulb
* **Bidirectional:** Connection goes both ways (↔).
* **Parity Flow:** Odd digits ⇒ Low digits.
* **Range Restrictions:**
  * Box 1 sum ≥ 25
  * Box 9 sum ≤ 18
  * Adjacent difference ≠ 1
HOW IT RENDERS IN CTC
  • Arrow Sums: Digits along the arrow sum to the bulb:
    • Cell A → Cell B → Bulb
  • Bidirectional: Connection goes both ways (↔).
  • Parity Flow: Odd digits ⇒ Low digits.
  • Range Restrictions:
    • Box 1 sum ≥ 25
    • Box 9 sum ≤ 18
    • Adjacent difference ≠ 1
Common HTML Entities Reference
Entity Code Result Entity Code Result Entity Code Result
→ → ← ← ↔ ↔
↑ ↑ ↓ ↓ ⇒ ⇒
≥ ≥ ≤ ≤ ≠ ≠
± ± • • ∞ ∞
4

Callout Quotes & Rule Notes

Begin lines with a greater-than symbol (`>`) to emphasize critical puzzle mechanics or cautionary notes.

WHAT YOU TYPE (MARKDOWN) 
> **Important Note:** Digits along an arrow may repeat if permitted by normal Sudoku rules (e.g. crossing across multiple boxes).

> **Negative Constraint:** All possible black and white Kropki dots are given.
HOW IT RENDERS IN CTC

Important Note: Digits along an arrow may repeat if permitted by normal Sudoku rules (e.g. crossing across multiple boxes).

Negative Constraint: All possible black and white Kropki dots are given.

5

Cell Coordinates, Notation & Monospace

Enclose grid coordinates or specific digits in backticks (`R1C1`) for monospaced highlighting.

WHAT YOU TYPE (MARKDOWN) 
The bulb of the thermo begins at `r3c5` and extends through `r4c5` to `r5c5`.

Given digits are placed at:
* `r1c1 = 7`
* `r9c9 = 4`
* Digits in cells `r2c2` and `r8c8` must sum to `10`.
HOW IT RENDERS IN CTC

The bulb of the thermo begins at r3c5 and extends through r4c5 to r5c5.

Given digits are placed at:

  • r1c1 = 7
  • r9c9 = 4
  • Digits in cells r2c2 and r8c8 must sum to 10.
7

Interactive Live Markdown Playground Live

Type or paste your Markdown text below to preview how it will appear on public CTC pages in real time.

EDIT MARKDOWN Auto-updates right column
LIVE PREVIEW (.ctc-markdown-content) 0 chars

Where is Markdown Supported in CTC?

Constraints & Rulesets

Rules and definitions edited in Admin appear formatted on /constraints/{slug}.

Puzzle Setters

Author biographies and notes appear formatted on /setters/{slug}.

Apps & Games

Feature lists and app descriptions appear formatted on /apps.

Categories

Category descriptions appear across catalog searches and puzzle filters.