Rules
The objective is to fill the grid with numbers from 1 to 9 in a way that the following conditions are met:
- Each row, column, and nonet contains each number exactly once.
- The sum of all numbers in a cage must match the small number printed in its corner.
- No number appears more than once in a cage. (This is the standard rule for killer sudokus, and implies that no cage can include more than 9 cells.)
In 'Killer X', an additional rule is that each of the long diagonals contains each number once.
Read more about this topic: Killer Sudoku
Famous quotes containing the word rules:
“Rules and particular inferences alike are justified by being brought into agreement with each other. A rule is amended if it yields an inference we are unwilling to accept; an inference is rejected if it violates a rule we are unwilling to amend. The process of justification is the delicate one of making mutual adjustments between rules and accepted inferences; and in the agreement achieved lies the only justification needed for either.”
—Nelson Goodman (b. 1906)
“It would be naive to think that peace and justice can be achieved easily. No set of rules or study of history will automatically resolve the problems.... However, with faith and perseverance,... complex problems in the past have been resolved in our search for justice and peace. They can be resolved in the future, provided, of course, that we can think of five new ways to measure the height of a tall building by using a barometer.”
—Jimmy Carter (James Earl Carter, Jr.)
“Now that the steam engine rules the world, a title is an absurdity, still I am all dressed up in this title. It will crush me if I do not support it. The title attracts attention to myself.”
—Stendhal [Marie Henri Beyle] (1783–1842)