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.
# MC521 - Desafios de Programacao I - 1s2021
# Contest: 07/05/2021
# Problema A: Face Detection

# leitura da altura e largura da imagem
n, m = map(int, input().split())

# inicializa matriz da imagem
imagem = []

# leitura da imagem em questao
for _ in range(n):
  imagem.append(list(input()))

# inicializa conjunto auxiliar e variavel resultado
face = set(('f', 'a', 'c', 'e'))
res = 0

# verifica quantidade de faces na imagem
for i in range(n-1):
  for j in range(m-1):
    # quadrado a ser analisado
    comp = set((imagem[i][j], imagem[i][j+1], imagem[i+1][j], imagem[i+1][j+1]))
    # compara com o conjunto 'face'
    if(comp == face): res += 1

# imprime o resultado
print(res)
   		 			    			 			  				  	