Inshi no heya is a type of logic puzzle

Logic puzzle

A logic puzzle is a puzzle deriving from the mathematics field of deduction.-History:The logic puzzle was first produced by Charles Lutwidge Dodgson, who is better known under his pen name Lewis Carroll, the author of Alice's Adventures in Wonderland...

 published by Nikoli

Nikoli

Nikoli Co., Ltd. is a Japanese publisher that specializes in games and, especially, logic puzzles. Nikoli is also the nickname of a quarterly magazine issued by the company...

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Rules

Inshi no heya is played on a rectangular grid with no standard size, broken into "rooms" by heavier borders. One of every room's dimensions will be a single cell; the length or width of the room varying by room.

Each room may run either horizontally or vertically, and has a small number appearing in its upper left corner.

The puzzle starts with all the cells empty.

The goal is to fill all the cells with nonzero single-digit numbers (1 through 9) such that:

• The numbers in each room, when multiplied together, equal the small number in the upper left corner of the room
• No number appears twice in a column or row

History

Inshi no heya first appeared in Puzzle Communication Nikoli #92. Although the creator named the puzzle insū bunkai (factorization), the editor replaced it with inshi no heya, which sounds less technical. It irregularly appears in the magazine since #109.