Logic Masters Deutschland e.V.

Rules:

Fill each cell in the grid with a digit 1-9. Digits cannot repeat in a row, column, or 3x3 box.

Draw three one-cell-wide loops of orthogonally connected cells. Each loop cannot touch itself, not even diagonally. Loops overlap at '+' indicators (either by meeting at right angles or by passing through each other), and cannot overlap in any other cells in the rest of the grid.

German Loop: One of the loops is a German Loop. Adjacent digits along a German Loop must differ by at least 5.

Parity Loop: One of the loops is a Parity Loop. Digits along a Parity Loop alternate odd/even.

Thermo-Loop: One of the loops is a Thermo-Loop. Whenever a Thermo-Loop travels vertically, the northern digit is greater than the southern digit. Whenever a Thermo-Loop travels horizontally, the eastern digit is greater than the western digit.

Squares: Cells containing a square cannot be on the German Loop (but may or may not be on other loops) and count the number of German Loop cells they touch (both orthogonally and diagonally).

Circles: Cells containing a circle cannot be on the Parity Loop (but may or may not be on other loops) and count the number of Parity Loop cells they touch (both orthogonally and diagonally).

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