Nikoli
Japanese logic puzzles, modelled and solved
2026 · 167 pp
Twenty-five Japanese pencil puzzles, Kakuro, Sudoku, Skyscrapers, Kakurasu, Takuzu, KenKen, Flow Free, Slitherlink, Hashi, Akari, Shikaku, Nurikabe, Masyu, Hitori, Fillomino, Heyawake, Shakashaka, Marupeke, Walls, L-Panel, BlockNumber, Searchlights, Numbrix, and Three-in-a-Row, each modelled as a constraint-satisfaction problem and solved by Google's CP-SAT.
The Japanese publisher Nikoli has given the world some of its finest logic puzzles. This volume takes twenty-five of them, sets out the rules, and solves each by formulating the puzzle as a constraint-satisfaction problem for Google’s CP-SAT solver.
Every chapter follows the same arc: problem statement, modelling narrative that turns the rules into constraints, CP-SAT implementation in Python, and a results table showing the solved grid. Where a puzzle has multiple difficulty settings, a toy puzzle and a harder one are both solved.
Puzzles covered: Kakuro, Sudoku, Skyscrapers, Kakurasu, Takuzu, KenKen, Flow Free, Squared Sudoku, Slitherlink, Hashi, Akari, Shikaku, Nurikabe, Masyu, Hitori, Fillomino, Heyawake, Shakashaka, Marupeke, Walls, L-Panel, BlockNumber, Searchlights, Numbrix, and Three-in-a-Row.