Sum-doku is an addition box. The numbers have to match with the sum, and each row has to have 1,2,3, and 4 in any order. However the same number cannot be in a row. And that is how Sum-doku works.
Sum-doku is an addition box. The numbers have to match with the sum, and each row has to have 1,2,3, and 4 in any order. However the same number cannot be in a row. And that is how Sum-doku works.