Killer Sudoku

How to play

1. Sudoku rules apply: each digit from 1 to 9 appears once per row, column and box.
2. The grid is split into cages, drawn with dotted lines. A cage’s small number is the sum of its cells.
3. A digit never repeats within a cage.
4. No digits are given at the start. Every grid has a single solution, found by logic.

Tips

• Start with small cages with extreme sums: 3 over two cells can only be 1 and 2.
• A row, a column or a box always adds up to 45: compare it with the cages inside.
• Note a cage’s possible combinations before placing a digit.