The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 subgrids that compose the grid (also called 'boxes', 'blocks', or 'regions') contains all of the digits from 1 to 9. On the top of each group You can see sum of the group. The group can has the same digits. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a unique solution.
Killer Sudoku game strategy
DESCRIPTION:
"Killer sudoku (also killer su doku, sumdoku, sum doku, sumoku, addoku, or samunamupure) is a puzzle that combines elements of sudoku and kakuro. Despite the name, the simpler killer sudokus can be easier to solve than regular sudokus, depending on the solver's skill at mental arithmetic, the hardest ones, however, can take hours to crack.A typical problem is to show killer sudoku, using colors to define the groups of cells. This problem is solved in sites with killer sudoku to play online. More often, puzzles are printed in black and white, with thin dotted lines used to outline the ""cages""
Killer sudoku puzzles were already an established variant of sudoku in Japan by the mid 1990s, where they were known as ""samunamupure."" The name stemmed from a Japanized form of the English words ""sum number place."" Killer sudokus were introduced to most of the English-speaking world by The Times in 2005.
Traditionally, as with regular sudoku puzzles, the grid layout is symmetrical around a diagonal, horizontal or vertical axis, or a quarter or half turn about the centre. This is a matter of aesthetics, though, rather than obligatory: many Japanese puzzle-makers will make small deviations from perfect symmetry for the sake of improving the puzzle. Other puzzle-makers may produce entirely asymmetrical puzzles.
There are many specialized journals and collections, books and instructions for solving them, many newspapers print Sudoku, but at the beginning of the most popular solution to Killer sudoku online."
Killer sudoku puzzles were already an established variant of sudoku in Japan by the mid 1990s, where they were known as ""samunamupure."" The name stemmed from a Japanized form of the English words ""sum number place."" Killer sudokus were introduced to most of the English-speaking world by The Times in 2005.
Traditionally, as with regular sudoku puzzles, the grid layout is symmetrical around a diagonal, horizontal or vertical axis, or a quarter or half turn about the centre. This is a matter of aesthetics, though, rather than obligatory: many Japanese puzzle-makers will make small deviations from perfect symmetry for the sake of improving the puzzle. Other puzzle-makers may produce entirely asymmetrical puzzles.
There are many specialized journals and collections, books and instructions for solving them, many newspapers print Sudoku, but at the beginning of the most popular solution to Killer sudoku online."
How to play
Control buttons:
choose a difficulty level (Killer Sudoku has 4 difficulty levels)
restart (start the game from the beginning)
step back
killer sudoku rules/pause
killer sudoku print
In addition to choosing a number, you can show possible numbers
Killer Sudoku game strategy
1.If there is only one empty cell left in the block of the same color, subtract the numbers of the block from the sum. So, if there is only one cell left in a small 3*3 square that does not have a number vertically or horizontally that we are checking, then this number is in this cell.
2.The sum in a row, in a column or in a small square of 3*3 is equal to 45 (1+2+3+4+5+6+7+8+9=45).
We find a cell that goes beyond the row(s), column(s) or small square(s) or, conversely, one cell is not enough to close the row(s), column(s) or small square(s)
3.There cannot be two identical numbers in one row and one column. So, if there is only one cell left in a small 3*3 square that does not have a number vertically or horizontally that we are checking, then this number is in this cell.
4.We remove possible numbers in the cell, avoiding repetition of numbers in each row, in each column and in each small square 3×3
5.If there are few empty cells left in any row, column or small square, put the possible numbers
6.If there are only two possible numbers in two cells in a row, column or small square, or three possible numbers in those cells, etc. then these numbers are not possible in other cells of this line or column or small square If these cells are also in one sum block, then their sum can be subtracted from the sum of the block and get the sum of the remaining cells of this sum block
7.Among the possible numbers, we leave only those that can give the required amount with other possible numbers
8.If a possible variant of the numbers of one block completely overlaps the possible numbers in the cell of another block, then this variant of the numbers is impossible
9.If there is possible number only in a row or column of a small square, then it will not be in other rows or columns of small squares, respectively (SUDOKU)
10.If no options are visible, then substitute a number and check (usually, where there are only two possible numbers) whether the assumption is correct. If the assumption is not true, another number is true (SUDOKU)
An example of a killer sudoku solution
1.If there is only one empty cell left in the block of the same color, subtract the numbers of the block from the sum.
2.The sum in a row, in a column or in a small square of 3*3 is equal to 45 (1+2+3+4+5+6+7+8+9=45).
We find a cell that goes beyond the row(s), column(s) or small square(s) or, conversely, one cell is not enough to close the row(s), column(s) or small square(s)
So only 4 can be here in the column (9+8+8+16=41. 45-41=4) :
So only 5 can be here in the small 3×3 square (2+15+7+16=40. 45-40=5) :
So only 9 can be here in the small 3×3 square (13+6+16+9+10=54. 54-45=9) :
So only 6 can be here in the small 3×3 square (7+3+11+12+18=51. 51-45=6) :
So only 6 can be here (13+7+17+7+15+16+9+10+19+26+7+16+12=174. 45*4=180-174=6) :
So only 1 can be here in the small 3×3 square (17+6+9+12=44. 45-44=1) :
So only 4 can be here (13+7+16+9+10+19+15+8+26+12+9+11+21=176. 45*4=180-176=4) :
and (6+4+9+1=20) 27-20=7 :
3.There cannot be two identical numbers in one row and one column. So, if there is only one cell left in a small 3*3 square that does not have a number vertically or horizontally that we are checking, then this number is in this cell.
Therefore, in the given example, the number 6 can only be in a darkened cell
4.We remove possible numbers in the cell, avoiding repetition of numbers in each row, in each column and in each small square 3×3
We choose the cell in our opinion with the smallest amount of possible numbers
We delete the numbers that are already in the row:
5.If there are few empty cells left in any row, column or small square, put the possible numbers
in the row 1: 3 empty cells, in the row 5: 2 empty cells:
6.If there are only two possible numbers in two cells in a row, column or small square, or three possible numbers in those cells, etc. then these numbers are not possible in other cells of this line or column or small square If these cells are also in one sum block, then their sum can be subtracted from the sum of the block and get the sum of the remaining cells of this sum block
in the column 5: 2,4,5
in the row 9: 45-21-13-3=8 (3+5+8, 4+4=8; 6+2=8)
but 4+4 it is impossible
in the color block of sum 9: 3+6, 6+3
in the row 9: 3+21+13+3=40. 45-40=5
7.Among the possible numbers, we leave only those that can give the required amount with other possible numbers If these cells are also in one sum block, then their sum can be subtracted from the sum of the block and get the sum of the remaining cells of this sum block
We remove possible numbers in the cell, avoiding repetition of numbers in each row, in each column and in each small square 3×3:
8.If a possible variant of the numbers of one block completely overlaps the possible numbers in the cell of another block, then this variant of the numbers is impossible If these cells are also in one sum block, then their sum can be subtracted from the sum of the block and get the sum of the remaining cells of this sum block
In the block, the option 3+8=11 is possible, but this number option (3,8) completely overlaps the possible options from the next block (sum = 12, possible numbers 3,8):
We remove possible numbers in the cell, avoiding repetition of numbers in each row, in each column and in each small square 3×3:
And
CONGRATULATIONS
KILLER SUDOKU RULES | Killer Sudoku Free Online | Print Killer Sudoku | No install or registration
choose a difficulty level (Killer Sudoku has 4 difficulty levels)
restart (start the game from the beginning)
step back
killer sudoku rules/pause
killer sudoku print
In addition to choosing a number, you can show possible numbers