Typique de la region
- Region sum lines
- Sandwiches
The brief
Normal sudoku rules apply. Blue lines are region sum lines, i.e. the digits on a blue line sum to the same value in each 3x3 region the line passes through. Different region sum lines can sum to different totals.All clues outside the grid are both X-sum and Sandwich clues. An X-sum clue indicates the sum of the first X digits in the respective row or column where X is the first digit seen from the clue. A Sandwich clue indicates the sum of all digits between 1 and 9 in the respective row or column.