Visual primer for first-time solvers

Shikaku,
shown not told.

Rectangle partition puzzle
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01
Goal: partition the grid into rectangles · each rectangle covers exactly one number · area = number.
Step01Meet the board

This is Shikaku.

A grid of cells with five numbers scattered around. Each number is a clue. Your task: draw one rectangle around each number so the rectangle's area equals the number. Every cell must be covered — no gaps, no overlaps, no other shapes.

Rules in play
  • Every cell must be covered by exactly one rectangle
  • Each rectangle contains exactly one number equal to its area
  • All regions must be true rectangles — no L-shapes or irregular polygons

Clue number

Each number equals the area (cell count) of the rectangle that must surround it. A cell marked 6 belongs to a 6-cell rectangle — 1×6, 2×3, or 3×2.

Rectangle colors

Each confirmed rectangle gets a distinct color. Thick dark border = boundary confirmed. Faded color = candidate being considered.

Candidate vs. placed

Orange border = rectangle being deduced this step. Dark border = confirmed and placed.

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