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 Go (1.6) (judge verdict: Wrong Answer)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)

	scanner.Scan()
	N, _ := strconv.ParseInt(scanner.Text(), 10, 0)
	scanner.Scan()
	M, _ := strconv.ParseInt(scanner.Text(), 10, 0)

	A := [50]string{}
	B := [50]string{}

	var i, j, y, x int64
	for i = 0; i < N; i++ {
		scanner.Scan()
		A[i] = scanner.Text()
	}
	for i = 0; i < M; i++ {
		scanner.Scan()
		B[i] = scanner.Text()
	}

	ret := false

	for i = 0; i < N-M; i++ {
		for j = 0; j < N-M; j++ {
			flg := true
			for y = 0; y < M; y++ {
				for x = 0; x < M; x++ {
					if A[i+y][j+x] != B[y][x] {
						flg = false
					}
				}
			}
			if flg {
				ret = true
			}
		}
	}

	if ret {
		fmt.Println("Yes")
	} else {
		fmt.Println("No")
	}
}