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.
n,m = map(int,input().split())
c,ff,aa,cc,ee = 0,0,0,0,0
for _ in range(n):
    s = input()
    if n<=1:
        break

    ff += s.count('f')
    aa += s.count('a')
    cc += s.count('c')
    ee += s.count('e')
    c = max(ff,aa,cc,ee,c)
print(c)
