Problem:
Score: 300 points

Problem Statement

We have a canvas divided into a grid with H rows and W columns. The square at the i-th row from the top and the j-th column from the left is represented as (i, j).

Initially, all the squares are white. square1001 wants to draw a picture with black paint. His specific objective is to make Square (i, j) black when s_{i, j}= #, and to make Square (i, j) white when s_{i, j}= ..

However, since he is not a good painter, he can only choose two squares that are horizontally or vertically adjacent and paint those squares black, for some number of times (possibly zero). He may choose squares that are already painted black, in which case the color of those squares remain black.

Determine if square1001 can achieve his objective.

Constraints

H is an integer between 1 and 50 (inclusive).

W is an integer between 1 and 50 (inclusive).

For every (i, j) (1 \leq i \leq H, 1 \leq j \leq W), s_{i, j} is # or ..

Input

Input is given from Standard Input in the following format:

H W
s_{1, 1} s_{1, 2} s_{1, 3} ... s_{1, W}
s_{2, 1} s_{2, 2} s_{2, 3} ... s_{2, W}
: :
s_{H, 1} s_{H, 2} s_{H, 3} ... s_{H, W}

Output

If square1001 can achieve his objective, print Yes; if he cannot, print No.

Sample Input 1

3 3
.#.
###
.#.

Sample Output 1

Yes

One possible way to achieve the objective is shown in the figure below. Here, the squares being painted are marked by stars.

Sample Input 2

5 5
#.#.#
.#.#.
#.#.#
.#.#.
#.#.#

Sample Output 2

No

square1001 cannot achieve his objective here.

Sample Input 3

11 11
...#####...
.##.....##.
#..##.##..#
#..##.##..#
#.........#
#...###...#
.#########.
.#.#.#.#.#.
##.#.#.#.##
..##.#.##..
.##..#..##.

Sample Output 3

Yes

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.text.DecimalFormat;

public class Main{
    public static void main(String[] args) throws Exception {
        //入力されたマス目を用意する
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = 0;
        System.out.print("キャンバスの大きさ:");
        String strn = br.readLine();//キャンバスの数入力
        //入力された文字を分解
        int w = 0;
        int j = 0;

        if(strn.length() == 3){
        w = Character.getNumericValue(strn.charAt(0));
        j = Character.getNumericValue(strn.charAt(2));
        }else{
        w = Integer.parseInt(strn.substring(0,strn.length()/2));
        j = Integer.parseInt(strn.substring(strn.length()/2+1,strn.length()));
        }

        String canvas[][] = new String[w][j];
        //wの数だけキャンバス入力
        for(int i = 0;i < w;i++){
        System.out.print((i+1)+"列目のマス:");
        String strCanvasLine = br.readLine();//キャンバスの数入力
            //配列に格納
            for(int x = 0;x<j;x++){
                canvas[i][x] = String.valueOf(strCanvasLine.charAt(x));
            }
        }

       
        
        //上下左右に１つでも＃があるのか網羅
        for(int wline = 0 ; wline < w ; wline++){
            for(int jline=0 ; jline < j ; jline++){
                if(canvas[wline][jline].equals("#")){//黒に塗りたい場所
                        boolean near = true;
                       //上下左右に場所があるかを確認
                        if(!(wline == 0)){//上がある
                            if(!(canvas[wline-1][jline].equals("#"))){
                                //上に黒がない
                                near = false;
                            }else{//上に黒がある
                                continue;
                            }
                        }

                        if(!(wline == w-1)){//下がある
                            if(!(canvas[wline+1][jline].equals("#"))){
                                //下に黒がない
                                near = false;
                            }else{//上に黒がある
                                continue;
                            }
                        }

                        if(!(jline == 0)){//左がある
                            if(!(canvas[wline][jline-1].equals("#"))){
                                //左に黒がない
                                near = false;
                            }else{//上に黒がある
                                continue;
                            }
                        }

                        if(!(jline == j-1)){//右がある
                            if(!(canvas[wline][jline+1].equals("#"))){
                                //右に黒がない
                                near = false;
                            }else{//上に黒がある
                                continue;
                            }
                        }

                        if(!(near)){
                            System.out.println("No");
                            System.exit(0);
                        }
                }
            }

        }

        System.out.println("Yes");
    }

}