How to solve Japanese-style logic puzzles

Overview

These guides discuss how to solve a variety of puzzles that are generally identified as Japanese-style puzzles. The most famous of this genre is Sudoku, which despite its name is an American invention. These puzzles have these basic common characteristics.

1. Language skills are not needed.
2. The puzzles are worked on a grid.
3. The rules are relatively simple.
4. Each puzzle has a unique solution that can be determined by logic alone.

However, there is quite a variety of puzzle types that fit within this category. A few require math skills (such as CalcDoku), but most do not. Some result in a picture (such as Paint-by-Numbers, which despite its name is a Japanese invention), while most are solved only for the pleasure of having done so.

These guides are intended to provide a basic overview of some of the more popular puzzle types. I will create guides as time allows, so check back!

Puzzle guides

Puzzle Overview: A listing of some popular puzzle types.

Fill-a-Pix: Draw a picture by blackening certain squares using single-number clues.

Hashi: Connect numbers in a grid by at most two lines.

Hitori: Blacken squares in a grid of numbers.

Link-a-Pix: Draw a picture by blackening certain squares using paired number clues.

Paint by Numbers: Draw a picture by blackening certain squares using row and column clues.

Slitherlink: Draw a single loop to satisfy the number clues.

Finding more puzzles

There are many sites that provide puzzles of these types and more, usually completely free or with some free samples. Unfortunately, some of these puzzles have multiple names, so searching can be a challenge. Here are two sites that I visit regularly:

1. Conceptis is a major contributor to Games Magazine, and also offers some puzzles for free. The online solving interface is excellent. This is especially recommended for picture-style puzzles, because the solutions are actual pictures rather than random designs.
2. BrainBashers offers daily free puzzles for many puzzle types.

All content copyright Paul and/or Valerie Hartzer, all rights reserved, except where indicated. Contact Paul Hartzer with comments. This file was last modified on Wednesday, January 27, 2010.