Coralfinder/en

Instructions

Blacken some cells to create a continuous wall (coral). Numbers outside the grid indicate the length of blackened cell blocks in the corresponding rows and columns, in increasing order. If there is more than one blackened block in a certain row or column, there must be at least one empty cell between the blocks. There cannot be any 2x2 blackened cells in the grid. The coral cannot touch itself and cannot have any holes inside it.