There is a landscape with hills and pits which have similar square shape. Each position in this landscape has a specified height. Max number of positions is 32000. Height is between 0 and 32000. For example: the first position has height 5, the second position has height 2. The landscape can be presented as a collection of heights. {5, 2, 3, 4, 5, 4, 0, 3, 1}
When rain happens, landscape is filled with water. Water is collected inside pits only between hills. For example: collected 9 squares of water.
