#include<bits/stdc++.h>
using namespace std;
#define pii pair<int, int>
#define ff first
#define ss second
#define ll long long
#define pll pair<ll, ll>
#define pb push_back
vector<int> dq[3010][3010];
int a[3021][3021];
int kto[9000001];
int cnt[3];
int pos[9000001];
vector<int> q[9000001];
void dfs(int v){
pos[v] = 1;
cnt[kto[v]] ++;
for(int to: q[v]){
if(pos[to]) continue;
dfs(to);
}
}
void solve(){
int n, m;
cin>>n>>m;
for(int i=1; i<=n; i++){
for(int j=1; j<=m; j++){
char c;
cin>>c;
a[i][j] = c;
}
}
int ls = 0;
for(int i=1; i<=n; i++){
for(int j=1; j<=m; j++){
if(j >= 3 and a[i][j] == 'W' and a[i][j-1] == 'G' and a[i][j - 2] == 'R'){
dq[i][j].pb(++ls);
dq[i][j-1].pb(ls);
dq[i][j-2].pb(ls);
kto[ls] = 1;
}
if(i >= 3 and a[i][j] == 'W' and a[i-1][j] == 'G' and a[i-2][j] == 'R'){
dq[i][j].pb(++ls);
dq[i-1][j].pb(ls);
dq[i-2][j].pb(ls);
kto[ls] = 2;
}
}
}
for(int i=1; i<=n; i++){
for(int j=1; j<=m; j++){
for(int x: dq[i][j]){
for(int y: dq[i][j]){
if(x != y) q[x].pb(y);
}
}
}
}
ll ans = 0;
for(int i=1; i<=ls; i++){
if(pos[i]) continue;
cnt[1] = cnt[2] = 0;
dfs(i);
ans += max(cnt[1], cnt[2]);
}
cout<<ans<<'\n';
}
int main(){
solve();
}
