A Study Of Sudoku Solving Algorithms: Backtracking and Heuristic

TL;DR

This study compares recursive backtracking and heuristic-based Sudoku-solving algorithms, demonstrating that heuristics significantly improve solving speed, especially on complex puzzles, across different difficulty levels.

Contribution

It provides a comparative analysis showing the superior performance of heuristic methods over backtracking in Sudoku solving across multiple difficulty levels.

Findings

Heuristic approach outperforms backtracking in solving speed.

Speedup ratios range from 1.27x to 2.91x depending on difficulty.

Heuristics are particularly effective for complex puzzles.

Abstract

This paper presents a comparative analysis of Sudoku-solving strategies, focusing on recursive backtracking and a heuristic-based constraint propagation method. Using a dataset of 500 puzzles across five difficulty levels (Beginner to Expert), we evaluated performance based on average solving time. The heuristic approach consistently outperformed backtracking, achieving speedup ratios ranging from 1.27x in Beginner puzzles to 2.91x in Expert puzzles. These findings underscore the effectiveness of heuristic strategies, particularly in tackling complex puzzles across varying difficulty levels.