Logic Masters Deutschland e.V.

Fill every white cell with a digit from 1 to 5.

Each horizontal and vertical run of five white cells must contain the digits 1 to 5 exactly once. Grey cells and the outer boundary separate the runs.

Each five-cell region outlined by thick lines must also contain the digits 1 to 5 exactly once.

Grey cells are not used. The small letters A to E mark the cells used for the solution code; fill these cells with digits as usual.