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.
import sys
import math

#to read string
get_string = lambda: sys.stdin.readline().strip()
#to read list of integers
get_int_list = lambda: list( map(int,sys.stdin.readline().strip().split()) )
#to read integers
get_int = lambda: int(sys.stdin.readline().strip())

#--------------------------------WhiteHat010--------------------------------------#
n,m = get_int_list()
matrix = []
s = {'f','a','c','e'}
count = 0

for i in range(n):
    matrix.append( list(get_string()) )

for i in range(n-1):
    for j in range(m-1):
        if set( [matrix[i][j], matrix[i][j+1], matrix[i+1][j], matrix[i+1][j+1] ]) == s:
            count += 1
print(count)
