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.
# Read the input
n, m = map(int, input().split())
image = []
for i in range(n):
  image.append(input())

# Iterate through the cells of the image
for i in range(n - 1):
  for j in range(m - 1):
    # Check the 2x2 square starting at (i, j)
    square = [image[i][j], image[i][j + 1], image[i + 1][j], image[i + 1][j + 1]]
    if set(square) == {'f', 'a', 'c', 'e'}:
      # The square is a face, so increment the count
      count += 1

# Print the result
print(count)
