#include <bits/stdc++.h>
#define ll long long
#define re register
#define il inline
#define cs const
using namespace std;

il int rd(){
    int out = 0 , flag = 1; char c = getchar();
    while(c < '0' || c >'9'){if(c == '-')flag = -1; c = getchar();}
    while(c >= '0' && c <= '9'){out = out * 10 + c - '0'; c = getchar();}
    return flag * out;
}

cs int N = 1e3 + 10;
int n , m , cnt;
char h[5][N][N];

int main(){
	n = rd() , m = rd();
	for(re int i = 1 , k = n ; i <= n ; i++ , k--)
		for(re int j = 1 , l = m ; j <= m ; j++ , l--)
			cin >> h[1][i][j] , h[2][j][i] = h[1][i][j] , h[3][k][l] = h[1][i][j] , h[4][l][k] = h[3][k][l];
	for(re int k = 1 ; k <= 4 ; k++)
		for(re int i = 1 ; i <= n ; i++)
			for(re int j = 4 ; j <= m ; j++)
				if(h[k][i][j - 3] == 'h' && h[k][i][j - 2] == 'e' && h[k][i][j - 1] == 'h' && h[k][i][j] == 'e') cnt++;
	cout << cnt;
	return 0;
}
```