Place the digits 0-9 in the grid so that every row, column, and 3x3 box contains every digit exactly once. To enable this, there is a single Schrödinger cell (S-cell) in each row, column and box, containing a superposition of two different digits. Each S-Cell is a Kakuro clue to the right or downwards, showing the sum of digits between that cell and the edge of the grid. A number outside the grid is also a Kakuro clue, showing the sum of digits between the edge of the grid and the next S-clue eg if an S-Cell contains the digits 12, the clue must be twelve or twenty one. Kakuro clues can be zero or have a leading zero. R2c1 contains an even digit.