Maximum Islands

You are mapping a distant planet with a satellite.

The satellite has taken one picture of the planet's surface. The photographed region is a grid. Each cell of the grid is land, water, or covered by clouds. A cell covered by clouds may be land or it may be water, and the picture does not tell you which.

An island is a set of connected land cells. Two cells are connected when they share an edge.

Given the picture, find the largest number of islands that is consistent with it.

The first line contains two integers $n$ and $m$ separated by a space. ($1 \le n, m \le 40$)

Each of the next $n$ lines contains $m$ characters describing the satellite picture. A land cell is written as 'L', a water cell as 'W', and a cell covered by clouds as 'C'.

Print one integer on a single line, the largest number of islands consistent with the given grid.