Normal sudoku rules apply. Digits outside the grid show the sum to the digits sandwiched between the 1 and the 9 in their row/column. Digits in circles must appear at least once in the four cells surrounding that circle.
Normal sudoku rules apply. Digits outside the grid show the sum to the digits sandwiched between the 1 and the 9 in their row/column. Digits in circles must appear at least once in the four cells surrounding that circle.