#include<bits/stdc++.h>
typedef long long ll;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
ll n,m,i,j,has;
char a[3030][3030];
int main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>n>>m;
for(i=1;i<=n;i++)
for(j=1;j<=m;j++)
cin>>a[i][j];
for(i=1;i<=n;i++)
for(j=1;j<=m;j++)
{
if(j+2<=m&&a[i][j]=='R'&&a[i][j+1]=='G'&&a[i][j+2]=='W')
{
// cout<<i<<" "<<j<<"\n";
a[i][j]='X';
a[i][j+1]='X';
a[i][j+2]='X';
has++;
}
if(i+2<=n&&a[i][j]=='R'&&a[i+1][j]=='G'&&a[i+2][j]=='W'&&(!(j>=3&&j<m&&a[i+1][j-1]=='R'&&a[i+1][j+1]=='W'&&a[i+2][j-2]=='R'&&a[i+2][j-1]=='G')))
{
a[i][j]='X';
a[i+1][j]='X';
a[i+2][j]='X';
has++;
}
}
cout<<has<<"\n";
}
