Шта је правило 45 у Судоку?
Последње ажурирано
Сваки комплетирани ред, колона и 3×3 кутија у Судаку садржи цифре 1 до 9 тачно једном. Пошто 1+2+3+4+5+6+7+8+9 = 45, свака комплетна јединица мора сумирати тачно 45 - Увијек.
Правило у Класичном Судокуу
У standard Sudoku 45 rule је најкорисније као verification tool. Ако сте попунили eight cells у row, ninth мора бити equal 45 минус sum of the other eight. Ово је another way of saying да missing digit је whatever was not yet placed - Но framing it as arithmetic може помоћи да се брзо ухвате errors и lock in the final cell of any unit with eight confirmed digits.
Правило у Killer Sudoku
The 45 rule is the cornerstone of Killer Sudoku strategy. In Killer every row, column, and 3×3 box still sums to 45, but you work with cage sums instead of given digits. Add up all cage sums entirely contained within a unit. If their total is less than 45, the difference equals the sum of cells crossing the unit boundary - Called innies and outies.
Example: cage sums inside a row add up to 38, and one cell from another cage crosses into the row. That cell must equal 45 - 38 = 7. You know the exact digit without any other deduction.
See the full explanation in the Killer Sudoku 45 rule guide.
Зашто је правило неприкосновено
The elegance of 45 comes from its mathematical certainty. No matter how a valid Sudoku is constructed, the constraint cannot be broken. Any solution that violates it is wrong. This makes it both a solving tool and an error-checking mechanism at every stage of the puzzle.