Place a digit from the specified list into some cells so that no digit 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 digit) 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.