#include <bits/stdc++.h>
#define loop(i,a,b) for(int i = (a); i < (b); i ++)
#define pb push_back
#define ins insert
#define pii pair<int,int>
#define ff first
#define ss second
#define op(x) cerr << #x << " = " << x << endl;
#define opa(x) cerr << #x << " = " << x << ", ";
#define ops(x) cerr << x;
#define entr cerr << endl;
#define spac cerr << ' ';
#define STL(x) cerr << #x << " : "; for(auto &qwe:x) cerr << qwe << ' '; cerr << endl;
#define ARR(x, nnn) cerr << #x << " : "; loop(qwe,0,nnn) cerr << x[qwe] << ' '; cerr << endl;
#define BAE(x) x.begin(), x.end()
#define unilize(x) x.resize(unique(BAE(x)) - x.begin())
#define unisort(x) sort(BAE(x)); unilize(x);
#define bye exit(0);
using namespace std;
typedef long long ll;
const int mxn = 3010;
const int INF = (int)(1e7);
const int nINF = -(int)(1e7);
char c[mxn][mxn];
vector<pii> EV;
const int mxN = (int)(9e6) + 3000;
bool vis[mxN], can[mxN];
vector<int> E[mxN];
int p[mxn][mxn];
int dfs(int st){
if(E[st].empty()) return 1;
vector<int> v[2], dp[3];
v[0].pb(st);
vis[st] = true;
v[1].pb(-1);
int dir = 0, tmp_dir = 0;
int two_son, three_son, only_son, son_cnt;
for(int ind = 0; ; ind++){
// opa(ind) op(dir)
// STL(v[0])
// STL(v[1])
if(v[0][ind] != -1 && v[1][ind] == -1) dir = 0;
else if(v[0][ind] == -1 && v[1][ind] != -1) dir = 1;
else if(v[0][ind] == -1 && v[1][ind] == -1) break;
v[0].pb(-1);
v[1].pb(-1);
tmp_dir = dir;
loop(j,0,2){
son_cnt = 0;
for(auto &i:E[v[tmp_dir][ind]]){
if(!vis[i]){
only_son = i;
son_cnt++;
vis[i] = true;
if(E[i].size() == 2){
two_son = i;
}
else if(E[i].size() == 3){
three_son = i;
}
}
}
if(son_cnt == 1){
v[tmp_dir][ind+1] = only_son;
}
else if(son_cnt == 2){
v[tmp_dir][ind+1] = three_son;
v[!tmp_dir][ind] = two_son;
}
tmp_dir = !tmp_dir;
if(v[tmp_dir][ind] == -1){
break;
}
}
}
int ret = 0;
int m = v[0].size();
dp[0].resize(m);
dp[1].resize(m);
dp[2].resize(m);
dp[0][0] = 0; // not take
dp[0][1] = (v[0][0] != -1); // take upper
dp[0][2] = (v[0][1] != -1); // take lower
loop(i,1,m){
dp[0][i] = max(max(dp[0][i-1], dp[1][i-1]), dp[2][i-1]);
dp[1][i] = max(dp[2][i-1], dp[0][i-1]) + 1;
dp[2][i] = max(dp[1][i-1], dp[0][i-1]) + 1;
if(v[0][i] == -1) dp[1][i] = nINF;
if(v[1][i] == -1) dp[2][i] = nINF;
ret = max(dp[0][i], max(dp[1][i], dp[2][i]));
}
// STL(v[0])
// STL(v[1])
return ret;
}
void check(int x, int y, int ind){
if(p[x][y] == 0){
p[x][y] = ind;
}
else{
EV.pb({p[x][y], ind});
}
}
int main(){
// freopen("in.txt", "r", stdin);
ios::sync_with_stdio(false); cin.tie(0);
int n, m;
cin >> n >> m;
loop(i,0,n){
loop(j,0,m){
cin >> c[i][j];
}
}
int now = 0;
loop(i,0,n){
loop(j,0,m){
if(c[i][j] == 'R' && c[i][j+1] == 'G' && c[i][j+2] == 'W'){
now++;
check(i, j, now);
check(i, j + 1, now);
check(i, j + 2, now);
can[now] = true;
}
if(c[i][j] == 'R' && c[i+1][j] == 'G' && c[i+2][j] == 'W'){
now++;
check(i, j, now);
check(i + 1, j, now);
check(i + 2, j, now);
can[now] = true;
}
}
}
unisort(EV);
for(auto &i:EV){
E[i.ff].pb(i.ss);
E[i.ss].pb(i.ff);
// opa(i.ff) op(i.ss);
}
int ans = 0;
loop(i,1,now + 1){
if((!vis[i]) && can[i]){
int tmp = dfs(i);
ans += tmp;
}
}
cout << ans << '\n';
}
