Normal sudoku rules apply. Each grey line is a "slow thermometer" with an invisible bulb at one end. Digits on a slow thermometer either increase or stay the same, as they move away from the bulb, but they never decrease.
Normal sudoku rules apply. Each grey line is a "slow thermometer" with an invisible bulb at one end. Digits on a slow thermometer either increase or stay the same, as they move away from the bulb, but they never decrease.