Brute Force Sudoku Solver

Algorithm:
Empty fields are filled in sequentially with the lowest possible digit.
If no digit is left, the previous field is changed to a higher match.
Failed if the first field has no match left. Done if all fields written.

black: given numbers, blue: results, red: conflicts

Please fill in given numbers!

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Transformations:

Turn counterclockwise
Mirror at column 5
Diagonal mirroring
Rotate 3 groups
Swap 2 groups
rOtate 3 columns
sWap 2 columns