3664: Bitmap--2018HBCPC K

RSYJ is a computer scientist. He has developed many useful image search tools. But now he has encountered some problems.

We use a matrix of H×H to represent a bitmap with H×H size, and each pixel of the 8-bit bitmap is represented by the integer between [0,255].

Now, RSYJ have a 8-bit bitmap A with n×n size, and a 8-bit bitmap B with m×m size.RSYJ uses an image processing software to copy bitmap B to some positions in bitmap A. Due to RSYJ's computer's error, the value of each pixel in the bitmap B is added with an offset k , which is an integer, but RSYJ doesn't know what k is.

Now your task is writing a program to help RSYJ find all positions of bitmap B in the bitmap A. To simplify the problem, you only need output how many positions of bitmap B in bitmap A.

For example, here are two bitmaps A and B:

A:

10 9 3

11 6 5

15 7 2

B:

4 3

5 0

Bitmap B was added with an offset: 6. It becomes:

10 9

11 6

Bitmap B was added with an offset: 2. It becomes:

6 5

7 2

So there are two positions of bitmap B in bitmap A.

The first line of the input gives two positive integers n,m, representing the size of bitmap A and the size of bitmap B, respectively.

The next n lines give the bitmap A. Each line contains n integers.

The next m lines give the bitmap B. Each line contains m integers.

1<=n<=400, 1<=m<=200, 0<=a_ij<=255, 0<=b_ij<=255

Please output an integer, representing the number of positions of bitmap B in bitmap A.

3 2
1 2 9
3 4 7
5 6 0
3 4
5 6

2