#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define ins insert
#define pb push_back
#define foru(i,a,b) for(int i=a;i<=b;i++)
#define ford(i,a,b) for(int i=a;i>=b;i--)
#define pii pair<int,int>
#define pll pair<ll,ll>
using namespace std;
int n,m,cnt,ans;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
cin>>n>>m;
vector<string> b(n+1);
for(int i=1;i<=n;i++){
string s;cin>>s;
b[i]=" "+s;
}
long long maxNodes = 1LL*m*(n/3) + 1LL*n*(m/3) + 5;
int MX = (int)maxNodes;
vector<int> pr(MX+5,0), sz1(MX+5,0), sz2(MX+5,0);
vector<char> vis(MX+5,0);
vector<vector<int>> id(n+2, vector<int>(m+2,0));
auto findp = [&](int u){
int root = u;
while(pr[root]!=root) root = pr[root];
while(u!=root){
int p = pr[u];
pr[u]=root;
u=p;
}
return root;
};
auto join = [&](int u,int v){
u = findp(u); v = findp(v);
if(u==v) return;
if(sz1[u]+sz2[u] > sz1[v]+sz2[v]) swap(u,v);
pr[u]=v;
sz1[v]+=sz1[u];
sz2[v]+=sz2[u];
};
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
if(i>=3 && b[i][j]=='W' && b[i-1][j]=='G' && b[i-2][j]=='R'){
cnt++;
pr[cnt]=cnt;
sz1[cnt]=1;
id[i][j]=cnt;
id[i-1][j]=cnt;
id[i-2][j]=cnt;
}
}
}
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
if(j>=3 && b[i][j]=='W' && b[i][j-1]=='G' && b[i][j-2]=='R'){
cnt++;
pr[cnt]=cnt;
sz2[cnt]=1;
if(id[i][j]!=0) join(id[i][j],cnt);
if(id[i][j-1]!=0) join(id[i][j-1],cnt);
if(id[i][j-2]!=0) join(id[i][j-2],cnt);
}
}
}
for(int i=1;i<=cnt;i++){
int r = findp(i);
if(!vis[r]){
vis[r]=1;
ans += max(sz1[r], sz2[r]);
}
}
cout<<ans;
return 0;
}
