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.
def main():
    read = lambda: tuple(map(int, input().split()))
    h, w = read()
    m = [input() for i in range(h)]
    def isFace(x, y):
        d = [m[y][x], m[y][x+1], m[y+1][x], m[y+1][x+1]]
        for c in "face":
            if not c in d:
                return False
        return True
        
    k = 0
    for y in range(h-1):
        for x in range(w-1):
            if isFace(x, y):
                k += 1
    print(k)
main()
