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# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
public class TM {
    public static void Main() {
        string[] read = new string[2];
        read = Console.ReadLine().Split(' ');
        int N = int.Parse(read[0]);
        int M = int.Parse(read[1]);
        string[,] A = new string[N,N];
        string[,] B = new string[M,M];
        for (int i = 0; i < N; i++) {
            string read2 = Console.ReadLine();
            for (int j = 0; j < N; j++) {
                A[i, j] = read2.Substring(j,1);
            }
        }
        for (int i = 0; i < M; i++) {
            string read2 = Console.ReadLine();
            for (int j = 0; j < M; j++) {
                B[i, j] = read2.Substring(j, 1);
            }
        }
        int shift = N - M;
        bool failed = false;
        bool cleared = false;
        for (int x = 0; x <= shift; x++) {
            for (int y = 0; y <= shift; y++) {
                failed = false;
                for (int i = 0; i < M; i++) {
                    for (int j = 0; j < M; j++) {
                        if (A[i + x, j + y] != B[i, j]) {
                            failed = true;
                            break;
                        }
                    }
                    if (failed) {
                        break;
                    }
                }
                if (failed == false) {
                    cleared = true;
                    break;
                }
            }
            if (cleared) {
                break;
            }
        }
        if (cleared) {
            Console.WriteLine("Yes");
        } else {
            Console.WriteLine("NO");
        }

    }
}