The developers of Looksery have to write an efficient algorithm that detects faces on a picture. Unfortunately, they are currently busy preparing a contest for you, so you will have to do it for them. 

In this problem an image is a rectangular table that consists of lowercase Latin letters. A face on the image is a 2 × 2 square, such that from the four letters of this square you can make word "face". 

You need to write a program that determines the number of faces on the image. The squares that correspond to the faces can overlap.
The first line contains two space-separated integers, *n* and *m* (1 ≤ *n*, *m* ≤ 50) — the height and the width of the image, respectively.

Next *n* lines define the image. Each line contains *m* lowercase Latin letters.
a=input().split()
per=input()
answer=0
for j in range(int(a[0])-1):
    per1=input()
    for i in range(int(a[1])-1):
        A=set()
        A.add(per[i+1])
        A.add(per[i])
        A.add(per1[i])
        A.add(per1[i+1])
        if len(A)==4:
            answer +=1
    per=per1
print((answer))
