import java.util.LinkedList;
import java.util.Scanner;

public class Main {
	
	 static int dx[]= {1,0,-1,0};//下，左，上，右
	 static int dy[]= {0,-1,0,1};
	
	public static class Point {
             int x;
             int y;
             int t;
             
//			public Point() {
//				super();
//			}

			public Point(int x, int y, int t) {
				super();
				this.x = x;
				this.y = y;
				this.t = t;
			}
			
	}
	
	public static char[][] bfs(int x,int y,char map[][],int s){
		int[][] v=new int[32][32];
		LinkedList<Point> q=new LinkedList<>();
		q.offer(new Point(x,y,0));
		v[x][y]=1;
		map[x][y]='#';
		while(!q.isEmpty()) {
			Point sp=q.poll();
			if(sp.t==s)
				break;
			for(int i=0;i<4;i++) {
				int xn=sp.x+dx[i];
				int yn=sp.y+dy[i];
				if(map[xn][yn]=='.'&&v[xn][yn]==0) {
					q.offer(new Point(xn,yn,sp.t+1));
					v[xn][yn]=1;
					map[xn][yn]='#';
				}
			}
		}
		return map;
	}
	public static void main...