/**
 *  Islands: Steven Zeil
 */

import java.awt.Point;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class Islands_sjz {

	private BufferedReader input;

	public Islands_sjz(BufferedReader input) {
		this.input = input;
	}

	public static void main(String[] args) throws FileNotFoundException, IOException {
		if (args.length > 0) {
			for (int i = 0; i < args.length; ++i) {
				try (BufferedReader input 
						= new BufferedReader(new FileReader(args[i])))
				{
					new Islands_sjz(input).solve();
				}
			}
		} else {
			BufferedReader input 
			    = new BufferedReader (new InputStreamReader(System.in));
			new Islands_sjz(input).solve();
		}

	}

	private void solve() throws IOException {
		String line = input.readLine();
		Scanner numInput = new Scanner(line);
		int nRows = numInput.nextInt();
		int nCols = numInput.nextInt();
		
		String[] map = new String[nRows];
		for (int i = 0; i < nRows; ++i) {
			map[i] = input.readLine();
		}
		
		solve (nRows, nCols, map);
		
		numInput.close();
	}

	private void solve(int nRows, int nCols, String[] map) {
		Queue<Point> q = new LinkedList<Point>();
		int[][] landMasses = new int[nRows][nCols];
		int counter = 0;

		for (int y = 0; y < nRows; ++y) {
			String row = map[y];
			for (int x = 0; x < nCols; ++x) {
				landMasses[y][x] = 0;
				char c = row.charAt(x);
				if (c == 'L') {
					q.add(new Point(x,y));
					++counter;
					landMasses[y][x] = counter;
				} if (c == 'W') {
					landMasses[y][x] = Integer.MAX_VALUE;
				}
			}
		}
		
		while (!q.isEmpty()) {
			Point p = q.remove();
			int massNumber = landMasses[p.y][p.x];
			check(landMasses, nRows, nCols, massNumber, p.x+1, p.y, q);
			check(landMasses, nRows, nCols, massNumber, p.x-1, p.y, q);
			check(landMasses, nRows, nCols, massNumber, p.x, p.y+1, q);
			check(landMasses, nRows, nCols, massNumber, p.x, p.y-1, q);
		}
		
		boolean[] remaining = new boolean[counter+1];
		Arrays.fill(remaining, false);
		counter = 0;
		for (int y = 0; y < nRows; ++y) {
			for (int x = 0; x < nCols; ++x) {
				int massNumber = landMasses[y][x];
				if (massNumber > 0 && massNumber < Integer.MAX_VALUE 
						&& !remaining[massNumber]) {
					++counter;
					remaining[massNumber] = true;
				}
			}
		}
		System.out.println(counter);
	}

	private void check(int[][] landMasses, int nRows, int nCols, int massNumber, int x, int y, Queue<Point> q) {
		if (x >= 0 && x < nCols && y >= 0 && y < nRows) {
			int mn = landMasses[y][x];
			if (massNumber > mn) {
				landMasses[y][x] = massNumber;
				q.add(new Point(x,y));
			}
		}
	}


}