The rules
Sukano puzzles follow the same rules with Sudoku:
- Only 1 to 9 appears in any cell of the board.
- No duplicated values in a row, a column, or in a block.
Sukano puzzle comes with 18 sets of hints, 1 set for each row and column:
- Each set of hint tells you the sums of the cells on that row or column.
- Red hint corresponds to the value of a single cell. Black hint corresponds to the sum of at least two cells.
- The hints are in order.
The puzzle can be solved completely by logic. No guessing is needed.
Below is an example of completed board, with separation point illustrated for reference.