<p>For those who struggle to solve a Sudoku puzzle, scientists have come to your rescue!<br /><br />Researchers at the University of Notre Dame have developed a mathematical algorithm that solves Sudoku puzzles very quickly, without any guessing or backtracking.<br /><br />Researchers, Zoltan Toroczka and Maria Ercsey-Ravasz, however, cannot only explain why some Sudoku puzzles are harder than others.<br /><br />Toroczkai and Ercsey-Ravasz from Romanias Babes-Bolyai University, began studying Sudoku as part of their research into the theory of optimisation and computational complexity.<br /><br />They note that most Sudoku enthusiasts use what is known as a “brute force” system to solve problems, combined with a good deal of guessing.<br /><br />Brute force systems essentially deploy all possible combinations of numbers in a Sudoku puzzle until the correct answer is found. While the method is successful, it is also time consuming. Instead, Toroczkai and Ercsey-Ravasz have proposed a universal analog algorithm that is completely deterministic (no guessing or exhaustive searching) and always arrives at the correct solution to a problem, and does so much more quickly.<br /><br />They discovered that the time it took to solve a problem with their analog algorithm correlated with the difficulty of the problem as rated by human solvers.<br /><br />This led them to develop a ranking scale for problem or puzzle difficulty. The scale runs from 1 through 4, and it matches up nicely with the “easy” through “hard” to “ultra-hard” classification currently applied to Sudoku puzzles.<br /><br />A puzzle with a rating of 2 takes, on average, 10 times as long to solve than one with rating of 1.<br /><br />According to this system, the hardest known puzzle so far has a rating of 3.6, and it is not known if there are even harder puzzles out there.<br /><br />“I had not been interested in Sudoku until we started working on the much more general class of Boolean satisfiability problems,” Toroczkai said.<br /><br />Toroczkai and Ercsey-Ravasz believe their analog algorithm potentially can be applied to a wide variety of problems in industry, computer science and computational biology.</p>.<p>The research experience has also made Toroczkai a devotee of Sudoku puzzles. The study findings appear in the journal Nature Scientific Reports.<br /></p>
<p>For those who struggle to solve a Sudoku puzzle, scientists have come to your rescue!<br /><br />Researchers at the University of Notre Dame have developed a mathematical algorithm that solves Sudoku puzzles very quickly, without any guessing or backtracking.<br /><br />Researchers, Zoltan Toroczka and Maria Ercsey-Ravasz, however, cannot only explain why some Sudoku puzzles are harder than others.<br /><br />Toroczkai and Ercsey-Ravasz from Romanias Babes-Bolyai University, began studying Sudoku as part of their research into the theory of optimisation and computational complexity.<br /><br />They note that most Sudoku enthusiasts use what is known as a “brute force” system to solve problems, combined with a good deal of guessing.<br /><br />Brute force systems essentially deploy all possible combinations of numbers in a Sudoku puzzle until the correct answer is found. While the method is successful, it is also time consuming. Instead, Toroczkai and Ercsey-Ravasz have proposed a universal analog algorithm that is completely deterministic (no guessing or exhaustive searching) and always arrives at the correct solution to a problem, and does so much more quickly.<br /><br />They discovered that the time it took to solve a problem with their analog algorithm correlated with the difficulty of the problem as rated by human solvers.<br /><br />This led them to develop a ranking scale for problem or puzzle difficulty. The scale runs from 1 through 4, and it matches up nicely with the “easy” through “hard” to “ultra-hard” classification currently applied to Sudoku puzzles.<br /><br />A puzzle with a rating of 2 takes, on average, 10 times as long to solve than one with rating of 1.<br /><br />According to this system, the hardest known puzzle so far has a rating of 3.6, and it is not known if there are even harder puzzles out there.<br /><br />“I had not been interested in Sudoku until we started working on the much more general class of Boolean satisfiability problems,” Toroczkai said.<br /><br />Toroczkai and Ercsey-Ravasz believe their analog algorithm potentially can be applied to a wide variety of problems in industry, computer science and computational biology.</p>.<p>The research experience has also made Toroczkai a devotee of Sudoku puzzles. The study findings appear in the journal Nature Scientific Reports.<br /></p>