This book cannot be returned. PRINT-ON-DEMAND; printing may add 2-4 business days.
Triplets ("One or All") is a logic puzzle invented by Naoki Inaba (Japan). The task consists of a rectangular or square grid divided into regions of exactly three cells. Some cells contain figures of 3 kinds: squares, circles, triangles.
The goal is to fill in each cell with figures. Each region must contain all identical or all different figures.
When two figures are orthogonally adjacent across a region boundary, the figures must be different.