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
input = sys.stdin.readline

n,m = map(int,input().strip().split())
a = []
for _ in range(n):
    a.append(input().strip())
let = {'f','a','c','e'}
c=0
for i in range(n):
    for j in range(m):
        try:
            if a[i][j] in let and a[i][j+1] in let and a[i+1][j] in let and a[i+1][j+1] in let:
                c+=1
        except Exception:
            pass
print(c)
