Normal sudoku rules apply. Each cage has a two-digit total to be placed by the solver inside the cage. Place the tens digit in the leftmost cell of the topmost row of the cage, then write the total from left to right. If the cage shape doesn’t allow a left-to-right placement, write the units digit directly below the tens digit instead. If the total consists of two identical digits (e.g., 22, 33, 44), write only a single digit. Digits may repeat within a cage, provided normal sudoku rules are not broken. Digits along an arrow sum to the digit in the attached circle.