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>
using namespace std;
char st[55][55];
char ch[55][55];
int main()
{
	int n,m;
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++)
	{   
	    scanf("\n");
		for(int j=1;j<=n;j++)
	    scanf("%c",&st[i][j]);
	}
	for(int i=1;i<=m;i++)
	{
	    scanf("\n");
		for(int j=1;j<=m;j++)
	    scanf("%c",&ch[i][j]);
	}
	bool flag;
	for(int i=1;i<=n;i++)
	for(int j=1;j<=n;j++)
	{
		if(i+m<=n&&j+m<=n)
		{
			int gg=0,kk;
			flag=true;
			for(int g=i+1;g<=i+m;g++)
			{
				gg++;
				kk=0;
				for(int k=j+1;k<=j+m;k++)
			    {
				    kk++;
				    if(ch[gg][kk]!=st[g][k])
				    {
				    	flag=false;
				    	break;
				    }
			    }
			    if(flag==false)
			    break;
			}
		}
		if(flag==true)
		break;
	}
	if(flag==true)
	printf("Yes");
	else
	printf("No");
	return 0;
} 
/*
3 2
#.#
.#.
#.#
#.
.#
*/