Pata is a variant of Tapa, in which the cells in a grid are split into either shaded or unshaded.
The objective is to divide the grid into shaded and unshaded cells, subject to the following rules:
- Clue cells cannot be shaded and indicate the number of consecutive cells unshaded around them. There must be at least one shaded cell between unshaded regions. ? is wild and can stand for any non-zero value.
- There must be one contiguous area of shaded cells, which is not allowed to contain 2x2 areas.
A standard 10x10 pata and its solution.