Shikaku

Divide the grid into rectangles so each contains exactly one number equal to its area.

How to Play

The grid contains numbered clues. Your goal is to partition the entire grid into non-overlapping rectangles where each rectangle contains exactly one clue and the clue's value equals the rectangle's area.

1. Navigate to a numbered clue and press Enter or Space to select it.
2. Press arrow keys to expand the rectangle in each direction.
3. Press Shift+Arrow to shrink a side if you overshot.
4. Press Enter or Space to confirm when the preview is green.
5. Press Backspace to cancel a draft or delete a placed rectangle.

Controls

Navigation Mode

Key	Action
Arrow keys / WASD / hjkl	Move cursor
Enter / Space	Select clue for expansion
Backspace	Cancel preview or delete rectangle at cursor
Ctrl+R	Reset puzzle
Ctrl+H	Toggle full help
Escape	Return to main menu

Expansion Mode (after selecting a clue)

Key	Action
Arrow keys / WASD / hjkl	Expand rectangle in that direction
Shift+Arrow / WASD / HJKL	Shrink rectangle from that side
Enter / Space	Confirm placement (green preview only)
Backspace	Cancel, discard preview

Modes

Mode	Grid	Max Rect	Description
Mini 5x5	5x5	5	Gentle introduction
Easy 7x7	7x7	8	Straightforward puzzles
Medium 8x8	8x8	12	Moderate challenge
Hard 10x10	10x10	15	Requires careful planning
Expert 12x12	12x12	20	Maximum challenge

Elo Difficulty

Named modes are compatibility presets. Use --difficulty <0..3000> to target a specific Elo difficulty for generated puzzles.

Quick Start

puzzletea new shikaku mini-5x5
puzzletea new shikaku easy-7x7
puzzletea new shikaku hard-10x10