The name of the puzzle is suko.
Load init-suko.
Ok.
The name of the action is write-1-to-9.
You can write a number that is between one and nine onto an empty location.
If the value of a location is absent then the location is empty.
The solution has four steps.
Load final-suko.
The name of the goal is all-filled.
Ok.
The goal is that all locations are filled.
If the value of a location is more than zero then the location is filled.
Load fail-suko.
If the value of a location is the value of another location then you lose.
Ok.
If the locations in a grouping are filled and the sum of the values of the grouping is not the value of a block that is above the grouping then you lose.
Ok.
If a block is filled and their locations are under the block then they are in a grouping.
If the blue locations are filled and the sum of the values of them is not ten then you lose.
Ok.
If the red locations are filled and the sum of the values of them is not nine then you lose.
Ok.
If the green locations are filled and the sum of the values of them is not twenty-six then you lose.
Ok.
Done.
No.