Today Sudoku contains very many types of variant Sudoku, more types of Sudoku puzzles are still under continuous development, please continue to pay attention to Sudoku today.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- Each number outside the grid is the sum of the first X numbers placed in the corresponding direction, where X is equal to the first number placed in that direction.
- There are some dots between cells. The numbers on each side of a dot must always be consecutive. Not all possible dots are marked.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- Each number outside the grid is the sum of the first X numbers placed in the corresponding direction, where X is equal to the first number placed in that direction.
- There are some dots between cells. The numbers on each side of a dot must always be consecutive. Not all possible dots are marked.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- Some thermometer shapes are placed in the grid. Digits are strictly increasing from the round bulb of the thermometer to each flat end.

- Some thermometer shapes are placed in the grid. Digits are strictly increasing from the round bulb of the thermometer to each flat end.

- A number at the edge of the diagram indicates the difference between the first and the last number in the corresponding row or column.

- A number at the edge of the diagram indicates the difference between the first and the last number in the corresponding row or column.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- Numbers with arrows indicate sum of the numbers in each direction.

- Numbers with arrows indicate sum of the numbers in each direction.

- Each number outside the grid is the sum of the first X numbers placed in the corresponding direction, where X is equal to the first number placed in that direction.

- Digits along each line are monotonically increasing or decreasing.

- Digits along each line are monotonically increasing or decreasing.

- The four corner boxes contain the same digit in symmetric positions about the centre.

- The four corner boxes contain the same digit in symmetric positions about the centre.

- A number between two cells indicates the quotient of the numbers in these cells. A number between four cells indicates the quotient between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- A number between two cells indicates the quotient of the numbers in these cells. A number between four cells indicates the quotient between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- Everywhere 2 odd and 2 even digits form a 2x2 checkerboard pattern, a Battenburg marking is given. A checkerboard pattern is a 2x2 area of cells where the top-left and bottom-right cells are of one type and the top-right and bottom-left cells are of another type. All possible dots are marked.

- Everywhere 2 odd and 2 even digits form a 2x2 checkerboard pattern, a Battenburg marking is given. A checkerboard pattern is a 2x2 area of cells where the top-left and bottom-right cells are of one type and the top-right and bottom-left cells are of another type. All possible dots are marked.

- In all cases where two digits have a consecutive value or one digit is two times as big as the other digit (or both), a greater than sign is placed. Digits have to be placed in accordance with the sign.

- In all cases where two digits have a consecutive value or one digit is two times as big as the other digit (or both), a greater than sign is placed. Digits have to be placed in accordance with the sign.

- A dot between two cells indicates that the sum of the numbers in these cells is 10 or 11. If no dot between two cells the sum of the numbers in these cells must not be 10 or 11.

- A dot between two cells indicates that the sum of the numbers in these cells is 10 or 11. If no dot between two cells the sum of the numbers in these cells must not be 10 or 11.

- A dot between two cells indicates that the sum of the numbers in these cells is 10 or 11. If no dot between two cells the sum of the numbers in these cells must not be 10 or 11.

- Digits along each line read the same from both directions.

- Digits along each line read the same from both directions.

- There are some dots between cells. The numbers on each side of a dot must always be consecutive. Not all possible dots are marked.

- The number in a cell with an arrow must not be repeated in a cell the arrow points to.

- The number in a cell with an arrow must not be repeated in a cell the arrow points to.

- A cross between two cells indicates that the product of the numbers in these cells is less than 10. A plus between two cells indicates that the sum of the numbers in these cells is less than 10. If the sum and product are less than 10, then there is a cross between these cells. If there is no sign between two cells, then both sum and product are at least 10.

- A cross between two cells indicates that the product of the numbers in these cells is less than 10. A plus between two cells indicates that the sum of the numbers in these cells is less than 10. If the sum and product are less than 10, then there is a cross between these cells. If there is no sign between two cells, then both sum and product are at least 10.

- Digits have to be place in accordance with the “greater than” signs.

- Digits have to be place in accordance with the “greater than” signs.