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.
输入描述:
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.


输出描述:
In the single line print the number of faces on the image.
示例1

输入

4 4<br />xxxx<br />xfax<br />xcex<br />xxxx<br />4 2<br />xx<br />cf<br />ae<br />xx<br />2 3<br />fac<br />cef<br />1 4<br />face<br />

输出

1<br />1<br />2<br />0<br />

备注:
In the first sample the image contains a single face, located in a square with the upper left corner at the second line and the second column: In the second sample the image also contains exactly one face, its upper left corner is at the second row and the first column.In the third sample two faces are shown: In the fourth sample the image has no faces on it.
加载中...