#include <bits/stdc++.h>
#define ff first
#define ss second
#define endl '\n'
using namespace std;
const long long INF = (long long) 1e18;
const int mod = (int) 1e9+7;
const int MAXN = (int) 3e3+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ll n, m;
char gr[MAXN][MAXN];
vector<int> adj[MAXN];
int name[MAXN][MAXN][2];
int ad = 0;
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);cout.tie(nullptr);
#ifdef Local
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/int.txt","r",stdin);
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/out.txt","w",stdout);
#endif
cin>>n>>m;
for(int i = 0; i < n; i++){
cin>>gr[i];
}
for(int i = 0; i < n - 2; i++){
for(int j = 0; j < m; j++){
if(gr[i][j] == 'R' && gr[i + 1][j] == 'G' && gr[i + 2][j] == 'W'){
name[i][j][0] = ++ad;
}
}
}
for(int i = 0; i < n; i++){
for(int j = 0; j < m - 2; j++){
if(gr[i][j] == 'R' && gr[i][j + 1] == 'G' && gr[i][j + 2] == 'W'){
name[i][j][1] = ++ad;
if(name[i][j][0]){
adj[name[i][j][0]].push_back(name[i][j][1]);
adj[name[i][j][1]].push_back(name[i][j][0]);
}
if(i && name[i - 1][j + 1][0]){
adj[name[i - 1][j + 1][0]].push_back(name[i][j][1]);
adj[name[i][j][1]].push_back(name[i - 1][j + 1][0]);
}
if(i > 1 && name[i - 2][j + 2][0]){
adj[name[i - 2][j + 2][0]].push_back(name[i][j][1]);
adj[name[i][j][1]].push_back(name[i - 2][j + 2][0]);
}
}
}
}
set<int> st;
for(int i = 1; i <= ad; i++){
st.insert(i);
}
int cnt = 0;
while(!st.empty()){
ll sim = *(st.begin());
cnt++;
for(int j: adj[sim]){
st.erase(j);
}
st.erase(st.begin());
}
cout<<cnt<<endl;
#ifdef Local
cout<<endl<<fixed<<setprecision(2)<<1000.0 * clock() / CLOCKS_PER_SEC<< " milliseconds ";
#endif
}
