Place a number from the specified list into some cells so that no number appears more than once in each row or column. Cells may remain empty. Numbers outside the grid indicate all sums of continuous groups of digits (including "sums" of a single number) along that row or column, in positional order. These groups are separated by empty cells.
Notes:Variants:
- Additionally: A question mark (?) indicates an unspecified (but non-zero) sum.
- Additionally: Some cells might be marked with a cross; do not put any numbers into those cells.