Sandwich X-tras
- Kropki dots
The brief
Standard sudoku rules apply: each row, column, and 3x3 box must contain all the digits from 1 to 9.
Clues outside the grid are dual: They are sandwich clues, giving the total of the digits between the 1 and the 9 in the row or column. They are also X-sums clues, giving the total of the first X digits in the row or column. X is the digit in the first cell seen from the clue.
A white dot separates digits with a difference of one. Not all dots are given.