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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;

class Main {
    public static void main(String[] args) {
        new Main().main();
    }

    public void main() {
        Scanner scanner = new Scanner(System.in);
        String[] nw = scanner.nextLine().split(" ", 2);
        int n = Integer.parseInt(nw[0]);
        int m = Integer.parseInt(nw[1]);

        char[][] a = new char[n][n];
        for (int i = 0; i < n; i++) {
            String line = scanner.nextLine();
            for (int j = 0; j < n; j++) {
                a[i][j] = line.charAt(j);
            }
        }

        char[][] b = new char[m][m];
        for (int i = 0; i < m; i++) {
            String line = scanner.nextLine();
            for (int j = 0; j < m; j++) {
                b[i][j] = line.charAt(j);
            }
        }

        boolean found = false;
        for (int startI = 0; startI <= n - m; startI++) {
            for (int startJ = 0; startJ <= n - m; startJ++) {
                if (this.matches(a, b, startI, startJ, n, m)) {
                    found = true;
                    break;
                }
            }
            if (found) {
                break;
            }
        }
        if (found) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }

    private boolean matches(char[][] a, char[][] b, int startI, int startJ, int n, int m) {
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < m; j++) {
                if (a[i + startI][j + startJ] != b[i][j]) {
                    return false;
                }
            }
        }
        return true;
    }
}