Parity 4x4s
- Killer cages
- Negative constraint
The brief
This sudoku grid is made up of four 4x4 sudokus, each made up from exactly four of the digits 1-9.
Digits cannot repeat in any row, column, or 2x2 box.
Each 4x4 sudoku is made up entirely of odd or even digits.
Digits in a cage sum to the given number.
Orthogonally adjacent digits cannot be consecutive.
