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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>

int main(void)
{
  int n,m,i,j,k,l,frag=1;
  char a[51][51],b[51][51];
  scanf("%d %d",&n,&m);
  for(i=0;i<n;i++)
    {
      scanf("%s",a[i]);
    }
  for(i=0;i<m;i++)
    {
      scanf("%s",b[i]);
    }
  for(i=0;i<n-m;i++)
    {
      for(j=0;j<n-m;j++)
	{
	  for(k=i;k<m+i;k++)
	    {
	      for(l=j;l<m+i;l++)
		{
		  if(b[k][l] != a[k][l])
		    {
		      frag = 0;
		      break;
		    }
		}
	      if(frag == 0)
		{
		  break;
		}
	    }
	  if(frag == 1)
	    {
	      printf("Yes\n");
	      return 0;
	    }
	}
    }
  printf("No\n");
  return 0;
}