Profile

Robert Charles

Contact Details

Bio

Sudoku rules


The puzzles are designed to fill the minutes of doing nothing with useful content. If you solve Sudoku in between work, the benefits will be obvious - the game makes the brain work when the body is resting.

What is Sudoku?


Free Sudoku easy is translated from Japanese as "stand-alone number". Because of the name, it is believed that the popular number puzzle came from Japan, but in fact Sudoku originated in America. Only decades later, it came to the Land of the Rising Sun, where it acquired its present name.

Crosswords in Japan did not take root - it is difficult to fill in the cells with hieroglyphs, so Sudoku immediately attracted attention and fell in love with the Japanese. Sudoku began to be printed in newspapers and magazines, and with the development of digital technology, electronic versions appeared and the puzzle took over the world. Now, in addition to Sudoku in printed collections, newspapers and magazines, you can use applications for a mobile phone or tablet.

Sudoku is a number puzzle that requires concentration, logical thinking and patience.

The essence of the game


Sudoku is based on a Latin square, each side of which consists of 9 cells. The square box is divided into 9 square blocks of 9 cells each. Some cells are already filled with numbers. To solve the puzzle, you must fill in all the empty fields according to certain rules.



There are several levels of Sudoku difficulty - the more cells are filled with numbers initially, the easier it is to solve the puzzle.

Sudoku is a logic game, so there is no need to guess. To solve the puzzle, one must connect deductive skills and use exclusion techniques. There are several approaches to solving Sudoku, the elimination method is the main, but not the only way to solve it.

There is no need to rush when solving Sudoku online. The puzzle perfectly develops attentiveness, patience and perseverance in adults and children. Sudoku is a great family game, with its help you can teach children to think logically and look for non-standard solutions.

The variety of Sudoku is huge. You can choose easy options for a few minutes or pick up a complex game that will take more than one day to work on. It all depends on the difficulty, skills and experience of solving Sudoku.

Fundamental rules


There are 81 cells in classic Sudoku. In a field divided into 9 blocks, the numbers from 1 to 9 must not be repeated:

- inside the block;
- in a horizontal line;
- in a vertical line.

When solving Sudoku, it is always important to pay attention to all 3 directions so that there are no coincidences in any of them.

For example, if the number 1 is in a 3 × 3 block, then it cannot be repeated inside it, but will be in other blocks. Also, it cannot be located in this row and in a column. But it will be repeated in adjacent vertical and horizontal lines.

Thus, each number from 1 to 9 is repeated 9 times within the entire puzzle. For a beginner, this can seem like a daunting and confusing task. But once you understand the basics of the puzzle, it will captivate you.

Interesting Facts

There are several interesting facts connected with Sudoku game:

In addition to the classic field size, there are also various variations - from 4 × 4 to 25 × 25.

There are variations of Sudoku with added regions and additional conditions.

In many countries, the board game Sudoku is released.
Some computer programs and mobile apps offer Sudoku with several solutions, while the classic version has only one solution for each scenario.

There are championships in Sudoku solving all over the world. The World Tournament is held by the International Puzzle Sports Federation.
Sudoku can be solved using a mathematical approach.

A group of scientists created a distributed computing project in order to find out the possibility of the existence of a uniquely solvable Sudoku with 16 clues. In 2012, they concluded that no such puzzle exists.
Sudoku originated from the Latin square math game, which was invented in the 18th century. Later, several digital crosswords were invented on its basis, one of which is Sudoku.

Sudoku was first published in the USA in 1979, but the game became popular only in the 90s thanks to regular publications in Japanese magazines and newspapers.

In 2005, scientists calculated the number of possible Sudoku variations for a 9 × 9 field. This number is 6 670 903 752 021 072 936 960 combinations. If you solve 1 Sudoku a day, then it will take about 19 million years to solve all the options.

In 2010, a record was set for the speed of solving Sudoku in the standard 9 × 9 size. At the championship in the Czech Republic, one of the participants solved the puzzle in 1.25 minutes.

The Japanese national team is the leader in victories in the international Sudoku tournament. The second most victorious team is the German team.

Sudoku is a good way to train your brain, logical thinking skills, and develop mindfulness. A useful and interesting activity that can fill the time on the way to work, traffic jams in the metropolis.