Problem:
Score : 200 points

Problem Statement

You are given an image A composed of N rows and N columns of pixels, and a template image B composed of M rows and M columns of pixels.

A pixel is the smallest element of an image, and in this problem it is a square of size 1×1.

Also, the given images are binary images, and the color of each pixel is either white or black.

In the input, every pixel is represented by a character: . corresponds to a white pixel, and # corresponds to a black pixel.

The image A is given as N strings A_1,...,A_N.

The j-th character in the string A_i corresponds to the pixel at the i-th row and j-th column of the image A (1≦i,j≦N).

Similarly, the template image B is given as M strings B_1,...,B_M.

The j-th character in the string B_i corresponds to the pixel at the i-th row and j-th column of the template image B (1≦i,j≦M).

Determine whether the template image B is contained in the image A when only parallel shifts can be applied to the images.

Constraints

1≦M≦N≦50

A_i is a string of length N consisting of # and ..

B_i is a string of length M consisting of # and ..

Input

The input is given from Standard Input in the following format:

N M
A_1
A_2
:
A_N
B_1
B_2
:
B_M

Output

Print Yes if the template image B is contained in the image A. Print No otherwise.

Sample Input 1

3 2
#.#
.#.
#.#
#.
.#

Sample Output 1

Yes

The template image B is identical to the upper-left 2 × 2 subimage and the lower-right 2 × 2 subimage of A. Thus, the output should be Yes.

Sample Input 2

4 1
....
....
....
....
#

Sample Output 2

No

The template image B, composed of a black pixel, is not contained in the image A composed of white pixels.

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <sstream>
#include <queue>
#include <map>
#include <vector>
#include <set>
#include <cstdlib>
#include <stack>

using namespace std;

typedef long long LL;
typedef double db;
#define FAST ios::sync_with_stdio(false);
const int MaxN = 105;
int n , m;
bool flag = false;
char mp1[55][55],mp2[55][55];
bool dfs(int x , int y)
{
	bool flag1 = true;
	for(int i = x , a = 1; i <= x + m ; i++,a++)
		for(int j = y,b = 1 ; j <= y + m ; j++,b++)
			{
			if(mp1[i][j] == mp2[a][b])continue;
			else flag1 = false;
			}
	return flag1;
	}
int main()
{
	cin >> n >> m;
	for(int i = 1 ; i <= n ; i++)
		for(int j = 1; j <= n ; j++)
			cin >> mp1[i][j];
	for(int i = 1; i <= m ; i++)
		for(int j = 1 ;j <= m ; j++)
			cin >> mp2[i][j];
	for(int i = 1 ; i <= n - m + 1 ; i++)
		for(int j = 1; j <= n - m + 1; j++)
			if(mp1[i][j] == mp2[1][1])if(dfs(i,j)){flag = true;break;}
	if(flag)cout << "Yes" << endl;
	else cout << "No" << endl;
	return 0;
	}