#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define ar array
#define pb push_back
#define ln '\n'
//#define int long long
using i64 = long long;
template <class F, class _S>
bool chmin(F &u, const _S &v){
bool flag = false;
if ( u > v ){
u = v; flag |= true;
}
return flag;
}
template <class F, class _S>
bool chmax(F &u, const _S &v){
bool flag = false;
if ( u < v ){
u = v; flag |= true;
}
return flag;
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, m; cin >> n >> m;
vector <string> s(n);
for ( auto &u: s ) cin >> u;
// 0 -> horizontal, 1 - vertical
vector <char> mp = {'R', 'G', 'W'};
vector <vector<int>> G;
int ct = 0;
auto ok = [&](int u, int v, char x){
return min(u, v) >= 0 && u < n && v < m && s[u][v] == x;
};
auto add = [&](int u, int v){
G[u].pb(v), G[v].pb(u);
};
unordered_map <int,unordered_map<int,unordered_map<int,int>>> p;
vector <ar<int,2>> Add;
int tot = 0;
for ( int i = 0; i < n; i++ ){
for ( int j = 0; j < m; j++ ){
vector <int> H;
bool h = false;
if ( j + 3 <= m && vector <char> {s[i][j], s[i][j + 1], s[i][j + 2]} == mp ){
p[i][j][0] = ct++; h = true;
if ( ok(i - 1, j + 1, 'R') && ok(i + 1, j + 1, 'W') ){
H.pb(p[i - 1][j + 1][1]);
}
if ( ok(i - 1, j + 2, 'G') && ok(i - 2, j + 2, 'R') ){
H.pb(p[i - 2][j + 2][1]);
}
}
if ( i + 3 <= n && vector <char> {s[i][j], s[i + 1][j], s[i + 2][j]} == mp ){
p[i][j][1] = ct++;
H.pb(p[i][j][1]);
}
if ( h > 0 ){
for ( auto &x: H ){
Add.pb({x, p[i][j][0]});
}
}
}
}
G.resize(ct);
for ( auto &[u, v]: Add ) add(u, v);
vector <int> us(ct);
vector <ar<int,2>> dp(ct, {1, 0});
auto dfs = [&](auto dfs, int u) -> void{
us[u] = true;
for ( auto &v: G[u] ){
if ( !us[v] ){
dfs(dfs, v);
dp[u][0] += dp[v][1];
dp[u][1] += dp[v][0];
}
}
chmax(dp[u][0], dp[u][1]);
};
int ans = 0;
for ( int i = 0; i < ct; i++ ){
if ( !us[i] ){
dfs(dfs, i);
ans += dp[i][0];
}
}
cout << ans;
cout << '\n';
}
