Tool/Solver to resolve Sudoku16x16. Hexadoku is a variant of classical Sudoku, also called giant sudoku, of size 16 by 16, with inner squares of 4x4. It can be filled with letters of hexadecimal characters.
Hexadoku (Sudoku 16x16) Solver - dCode
Tag(s) : Number Games
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Hexadoku (Sudoku 16x16) Solver
Solve a Hexadoku grid
16x16 Sudoku Generator
Answers to Questions (FAQ)
What is Hexadoku? (Definition)
Hexadoku (or Sudoku 16x16 or hexasudoku or hexa-wordoku) is a variation of classic Sudoku defined on a 16x16 grid, or 256 squares, structured into 16 4x4 regions.
The goal is to fill the grid with a set of 16 distinct symbols (numbers, letters, or other characters) such that each symbol appears exactly once in each row, each column, and each region.
How to fill the Hexadoku 16x16 grid?
Filling a Hexadoku grid involves using a set of 16 distinct symbols. These symbols can be represented in various ways, provided they are all unique:
— 1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G: the usual sudoku numbers (from 1 to 9) followed by the first letters of the alphabet.
— 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F: hexadecimal digits (base 16)
— A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P: the first 16 letters of the alphabet (variant letters can be used to guess words)
dCode allows all alphanumeric characters, both the letters A-Z and the numbers 0-9. On the other hand, the numbers 10,11,12,13,14,15,16 are prohibited, replace them with letters if necessary.
It is possible to copy and paste and/or directly type the values in the boxes (space for empty).
Example: Copy the content in the first cell 89 4 3 1 DA2 6 DA B E 5C 8 1CF 5 EB 6 4 32 AC 9 4 1 A 4 6 E7 8 E 6 5 7 0F4 6 7C 9 D87 E 6 5A 2 08 5 E F 45 2FA 8369 D A3720 F A D5 C 4 1D04 AF C E8 B C1 to get:
| 8 | 9 | ␣ | 4 | ␣ | 3 | ␣ | 1 | ␣ | D | A | 2 | ␣ | 6 | ␣ | ␣ |
| ␣ | ␣ | ␣ | D | A | ␣ | ␣ | B | ␣ | E | ␣ | 5 | C | ␣ | ␣ | 8 |
| ␣ | ␣ | 1 | C | F | ␣ | 5 | ␣ | ␣ | ␣ | ␣ | ␣ | E | B | ␣ | ␣ |
| 6 | ␣ | ␣ | ␣ | ␣ | ␣ | 4 | ␣ | ␣ | ␣ | ␣ | ␣ | 3 | 2 | ␣ | A |
| C | ␣ | ␣ | ␣ | ␣ | 9 | ␣ | ␣ | ␣ | 4 | ␣ | 1 | ␣ | ␣ | A | ␣ |
| ␣ | 4 | ␣ | ␣ | ␣ | ␣ | 6 | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | E |
| 7 | ␣ | 8 | ␣ | ␣ | ␣ | ␣ | ␣ | E | ␣ | ␣ | ␣ | 6 | ␣ | ␣ | 5 |
| ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | 7 | ␣ | 0 | F | 4 | ␣ |
| ␣ | ␣ | ␣ | 6 | ␣ | ␣ | ␣ | ␣ | 7 | C | ␣ | ␣ | ␣ | 9 | ␣ | ␣ |
| D | 8 | 7 | ␣ | ␣ | E | ␣ | 6 | ␣ | ␣ | 5 | A | ␣ | ␣ | ␣ | ␣ |
| ␣ | ␣ | 2 | ␣ | 0 | 8 | ␣ | 5 | ␣ | ␣ | E | ␣ | F | ␣ | ␣ | ␣ |
| 4 | 5 | ␣ | ␣ | 2 | F | A | ␣ | 8 | 3 | 6 | 9 | ␣ | ␣ | D | ␣ |
| ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ | A | 3 | 7 | 2 | 0 | ␣ | ␣ | ␣ | F |
| ␣ | ␣ | A | ␣ | D | 5 | ␣ | C | ␣ | ␣ | ␣ | ␣ | 4 | ␣ | ␣ | ␣ |
| ␣ | 1 | D | 0 | 4 | ␣ | ␣ | ␣ | ␣ | A | F | ␣ | ␣ | ␣ | C | ␣ |
| ␣ | ␣ | ␣ | E | 8 | ␣ | B | ␣ | C | 1 | ␣ | ␣ | ␣ | ␣ | ␣ | ␣ |
How does the step by step works?
The Hexadoku solver uses a combination of logical deduction and algorithmic search to complete the grid.
Initially, it uses logical rules similar to those employed by a human: analyzing constraints on rows, columns, and regions to eliminate possibilities and deduce certain values.
When these deductions are no longer sufficient, the solver uses a search method called backtracking: it tests a hypothesis for a cell, continues solving, and then goes back if a contradiction appears.
The steps of logical deduction can be displayed to explain the progress. However, the testing and backtracking phases are generally not detailed for readability.
Depending on the initial grid, there may be one or more valid solutions. The solver can display one or more depending on its configuration.
How many possible Hexadoku grids are there?
The exact number of complete Hexadoku puzzles is currently unknown.
By analogy, 9x9 Sudoku has approximately 6.67 Ă— 10^21 valid puzzles.
For Hexadoku, this number is significantly higher due to the increased size and number of constraints.
Source code
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