# Ludii and XCSP: Playing and Solving Logic Puzzles

## TL;DR

This paper explores the use of the XCSP formalism to solve logic puzzles described in the Ludii system, leveraging constraint programming to address NP-Complete puzzles like Sudoku.

## Contribution

It introduces a method to represent Ludii logic puzzles in XCSP format, enabling the use of various CSP solvers for efficient problem solving.

## Key findings

- Effective translation of Ludii puzzles into XCSP format
- Demonstrated solving of complex puzzles using CSP solvers
- Enhanced flexibility in puzzle solving approaches

## Abstract

Many of the famous single-player games, commonly called puzzles, can be shown to be NP-Complete. Indeed, this class of complexity contains hundreds of puzzles, since people particularly appreciate completing an intractable puzzle, such as Sudoku, but also enjoy the ability to check their solution easily once it's done. For this reason, using constraint programming is naturally suited to solve them. In this paper, we focus on logic puzzles described in the Ludii general game system and we propose using the XCSP formalism in order to solve them with any CSP solver.