Logic Masters Deutschland e.V.

Normal sudoku rules apply.

To complete the puzzle, you must color all the uncolored squares red or blue.  The given colored squares are purple, and for all rules purposes, a purple square counts as both red and blue.  All purple cells are given.

Your coloring must satisfy all of the following:

1) The group of red squares is orthogonally connected.  The same is true of the group of blue squares.

2) No 2x2 region is either all red or all blue.  

3) The numbers on the rows indicate the sum of the red cells in that row.  The numbers in the columns give the sum of the blue cells in that column.

4) If a circled cell is red, it gives the number of red cells in its box.  If it is blue, it gives the number of blue cells in its box. 

To clarify, below is a completed grid (for a hypothetical puzzle) that satisfies all of the above rules:

The partial grid below includes many examples of things that are not allowed.

The things that are wrong are:

The red cells in row 1 do not sum to 22.

The red cells in row 2 do not sum to 21, because the purple cell is red, so they actually sum to 7+4+6+3+5=25

In box 1, there is a 2x2 all blue region (because the purple cell is also blue).

In box 2, the circled purple cell is both red and blue, so it should give the number of red cells, as well as the number of blue cells. The number of red cells is correct, it is 7. However, this box has only 3 blue cells, so the circled digit is wrong.

In box 3, the three red cells have been isolated from the other red cells, so the group of red cells is not orthogonally connected.

That's all, have fun, leave a comment if you enjoy the puzzle!

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