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 = input().split(' ')
n = int(n)
m = int(m)

# print(n, m)
f = 0
a = 0
c = 0
e = 0
# print(f, a, c, e)

for i in range(n):
    str1 = input()
    # print(str1)
    for s in str1:
        # print(s)
        if s == 'f':
            f+=1
        elif s == 'a':
            a+=1
        elif s == 'c':
            c+=1
        elif s == 'e':
            e+=1
        else:
            continue
        # print(f, a, c, e)

# print(f, a, c, e)
print(max(f, a, c, e))