Divide the grid into ominoes (regions of orthogonally connected cells), so that no two ominoes of the same size share an edge. Each cell contains a number equal to its omino's size. After the regions are placed, it must be possible to shade the regions one of two colours such that any two regions touching on an edge have different colouring. One or more arrows in a cell indicate that the number in the cell equals the number of cells of the same shading in all of the directions combined.