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.
#!/usr/bin/env python
# -*- coding: utf-8 -*-

face = set('face')
n,m = map(int,input().split())
faces = []
for i in range(n):
    faces.append(list(input()))

count = 0
for i in range(n):
    for j in range(m):
        dxdy = [(0,0),(0,1),(1,1),(1,0)]
        f = []
        for dx,dy in dxdy:
            if 0 <= dy + i < n and 0 <= dx + j < m:
                f.append(faces[i + dy][j + dx])
        if face == set(f):
            count += 1
print(count)
