What is time complexity for Sudoku?

Time Complexity:

The time complexity for solving sudoku using backtracking is tricky to calculate. The worst case time complexity is equal to the number of possible board configurations which is 9^81. This can be even boiled down to 9^k where k is the number of empty cells in the initial board configuration.

What is the time complexity of Sudoku brute force algorithm?

Time Complexity: The backtracking algorithm takes O(9^m) time complexity in the worst case since for every unfilled cell there are 9 possibilites to explore and there are m unfilled cells in the sudoku. For Brute force approach: Worst Case Time Complexity: O(9^m)

What is the algorithm for Sudoku problem?

The Algorithm

One algorithm to solve Sudoku puzzles is the backtracking algorithm. Essentially, you keep trying numbers in empty spots until there aren't any that are possible, then you backtrack and try different numbers in the previous slots.

What is the most efficient algorithm to solve Sudoku?

Backtracking algorithm is the fastest algorithm to solve sudoku puzzles, It is by far the fastest compared to the other two methods. Also, let's note that each algorithm was faster with harder problems than with easier problems.

What is the mathematical structure of Sudoku?

A Shidoku is a 4 × 4 Sudoku board with 2 × 2 blocks. Each row, column, and block contains the numbers 1 through 4. In a Shidoku, there are 4 ∗ 3 ∗ 2 ∗ 1 = 24 ways to fill in the first block. Let x be the number of ways to fill in the remaining 3 blocks; this gives the total number of Shidoku squares as 24x.

Calculating Time Complexity | New Examples | GeeksforGeeks

What is the fastest time complexity algorithms?

Constant-Time Algorithm - O (1) - Order 1: This is the fastest time complexity since the time it takes to execute a program is always the same. It does not matter that what's the size of the input, the execution and the space required to run this will be the same.

What is the fastest Sudoku time easy mode?

7. The Guinness World Record for the fastest solve of a 'Very Easy' level Sudoku is held by American player Thomas Snyder. He completed the puzzle in a blazing 1 minute and 23.93 seconds! 8.

Why Sudoku is NP-complete?

The generalised Sudoku problem is an NP-complete problem which, effectively, requests a Latin square that satisfies some additional constraints. In addition to the standard requirement that each row and column of the Latin square contains each symbol precisely once, Sudoku also demands block constraints.

Is a 9x9 Sudoku NP-complete?

Sudoku is NP-complete when generalized to a n × n grid however a standard 9 × 9 Sudoku is not NP- complete.

Can you solve Sudoku mathematically?

The puzzle does not depend on the fact that the nine placeholders used are the digits from 1 to 9. Any nine symbols would serve just as well to create and solve the puzzles. In fact, mathematical thinking in the form of logical deduction is very useful in solving Sudokus.

Can you complete Sudoku without guessing?

Can all Sudoku puzzles be solved without guessing? According to Sudoku Of The Day, “Sudoku is a puzzle involving logic—no arithmetic or guessing is required!” While you can, guess, of course, if your guess is wrong, it will throw off the rest of the puzzle and you'll need to start over.

What is the smartest way to play Sudoku?

Is Sudoku good for the brain?

Sudoku keeps your brain active and reduces the risk of Alzheimer's, a most common cause of dementia that affects a person's thinking and behavioural skills. Stimulates your mind: The game works on your logical thinking process as you are absorbed in solving a puzzle and eventually improve your number skills.

What is the fewest number to solve Sudoku?

The fewest clues required for a proper Sudoku is 17, but not all completed grids can be reduced to a proper 17 clue Sudoku. About 49,000 unique (non-equivalent) Sudokus with 17 clues have been found. (A proper Sudoku has only one solution).

What is the most common time complexity?

Time complexity describes how the runtime of an algorithm changes depending on the amount of input data. The most common complexity classes are (in ascending order of complexity): O(1), O(log n), O(n), O(n log n), O(n²).

Which time complexity is best?

1. O(1) has the least complexity. Often called “constant time”, if you can create an algorithm to solve the problem in O(1), you are probably at your best.

What is the rule of 45 in Sudoku?

The 45 rule is a basic solving-technique in Killer Sudoku. Each house (row, column, nonet) must add to 45 (the sum of the digits 1 through 9).

Do Sudoku players have high IQ?

From this case study it can be concluded that an individual who is skilled at solving Sudoku puzzles likely has a high general IQ. The results of the weak correlation between Sudoku scores and the WAIT test indicates that in some cases a high Sudoku doesn't necessarily mean a high general IQ.

Does Sudoku fight dementia?

“Just sitting down and doing Sudoku isn't probably going to be the one key thing that's going to prevent you from developing Alzheimer's disease,” she said. Moreover, doing only one type of puzzle or another is not the key either. The brain needs to be exercised, just like any other muscle in the body.

What are the 3 rules of Sudoku?

What is the swordfish technique in Sudoku?

A Swordfish is a 3 by 3 nine-cell pattern where a candidate is found on three different rows (or three columns) and they line up in the opposite direction. Eventually we will fix three candidates somewhere in those cells which excludes all other candidates in those units.

What is a hidden triple in Sudoku?

"Hidden triples" applies when three cells in a row, column, or 3x3 block contain the same three Notes. These three cells also contain other candidates, which may be removed from them. It will be easier to understand this technique if you look at the example. Take a look at the highlighted cells.

What happens if I solve a Sudoku daily?

The more you play, the better you become. If you play Sudoku daily, you will start to discover that you have almost a sort of “sense memory” for the puzzle grid – you will start to see patterns emerging and develop the ability to seize opportunities more quickly.