Mouse

import java.util.*;
public class Mouse {

	/**
	 * @param args
	 */

	private boolean found = false;
	public int si, sj, ei, ej;
	public boolean vist(char[][] bear, int i, int j, int R, int C){
		if (this.found) {
			return true;
		}

		if (bear[i][j] == 'u') {
			return this.found;
		}

		bear[i][j] = 'u';
		if(i == ei && j == ej){
			this.found = true;
		}

		if(j < C - 1 && bear[i][j+1] == '-')
			vist(bear, i, j+1, R, C);
		if(i < R - 1 && bear[i+1][j] == '-')
			vist(bear, i+1, j, R, C);
		if((j -1) >= 0 && bear[i][j-1] == '-')
			vist(bear, i, j-1, R, C);
		if((i - 1)>=0 && bear[i-1][j] == '-')
			vist(bear, i-1, j, R, C);

		return this.found;
	}
	public static void main(String[] args) {
		// TODO Auto-generated method stub

		Scanner scanner = new Scanner(System.in);
		int R, C;
		R = Integer.parseInt(scanner.nextLine());
		C = Integer.parseInt(scanner.nextLine());
		char[][] bear = new char[R][C];
		int i = 0;
		Mouse m = new Mouse();
		for (int k = 0; k < R; k++) {
			String s = scanner.next();
			char[] ss = s.toCharArray();
			for(int j = 0; j < C; j++){
				bear[i][j] = ss[j];
				if(bear[i][j] == 'B'){
					m.si = i;
					m.sj = j;
				}
				if(bear[i][j] == 'H'){
					m.ei = i;
					m.ej = j;
				}
			}
			i++;
		}
		if(m.vist(bear, m.si, m.sj, R, C))
			System.out.println("Y");
		else
			System.out.println("N");
	}
}