Logic Masters Deutschland e.V.

A bank of shapes is given with the grid (two of each tetromino shape). Place each of the shapes exactly once into the grid by shading some cells, with rotations and reflections allowed. No two shapes can overlap or be orthogonally adjacent, and all of the unshaded cells must be orthogonally connected.

Black circles in the grid represent cells that must be shaded, and white circles represent cells that must be unshaded.

Digits in shaded cells show the number of unshaded cells in the 8 cells adjacent to it (orthogonally and diagonally, like minesweeper) and digits in unshaded cells show the number of shaded cells in the 8 cells adjacent to it.