Codeforces 549A. Face Detection[模擬]

A. Face Detection

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

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.

Input

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.

Output

In the single line print the number of faces on the image.

Examples

input

4 4
xxxx
xfax
xcex
xxxx

output

1

input

4 2
xx
cf
ae
xx

output

1

input

2 3
fac
cef

output

2

input

1 4
face

output

0

Note

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.

---

題意：四個格子裡出現face四個字母

---

我是用了個vis陣列，題解是給四個格子字母排序與acef對比

//
//  main.cpp
//  cf549a
//
//  Created by Candy on 9/15/16.
//  Copyright © 2016 Candy. All rights reserved.
//

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
using namespace std;
const int N=55;
int n,m,ans=0;
int a[N][N],vis[30];
char s[N];
int main(int argc, const char * argv[]) {
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++){
        scanf("%s",s);
        for(int j=0;j<m;j++)
            a[i][j+1]=s[j]-'a';
    }
    
    for(int i=1;i<=n-1;i++)
        for(int j=1;j<=m-1;j++){
            memset(vis,0,sizeof(vis));
            vis[a[i][j]]++;
            vis[a[i+1][j]]++;
            vis[a[i][j+1]]++;
            vis[a[i+1][j+1]]++;
            if(vis[0]&&vis['f'-'a']&&vis['c'-'a']&&vis['e'-'a']) ans++;
        }
    printf("%d",ans);
    return 0;
}