#include <bits/stdc++.h>
#define all(a) a.begin(),a.end()
#define pb push_back
using namespace std ;
const int maxn = 3002 , maxq =1e6 , inf = 1e9 + 100 , mod = 1e9 + 7 ;
char c[maxn][maxn] ;
vector <int> G[maxq] ;
vector <int> vec[maxn][maxn] ;
int ans[2] , dp[maxq][2];
bool mark[maxq] ;
void dfs(int v ){
mark[v] = 1;
dp[v][1] = 1;
for(int i = 0 ; i < (int)G[v].size() ; i++){
int u = G[v][i] ;
if(mark[u] == 1)continue ;
dfs(u);
dp[v][0] += max(dp[u][1] , dp[u][0]) ;
dp[v][1] += dp[u][0] ;
}
}
signed main(){
int n , m ;
cin >> n >> m ;
for(int i = 1; i <= n ; i++){
for(int j = 1; j <= m ; j++){
cin >> c[i][j] ;
}
}
int cnt = 0 ;
for(int i =1 ; i <= n ; i++){
for(int j = 1; j <= m ; j++){
if(i <= (n-2) && c[i][j] == 'R' && c[i+1][j] == 'G' && c[i+2][j] == 'W'){
cnt++;
// cout << i << " " << j << "D\n";
vec[i][j].pb(cnt);
vec[i+1][j].pb(cnt);
vec[i+2][j].pb(cnt);
}
if(j <= (m-2) && c[i][j] == 'R' && c[i][j+1] == 'G' && c[i][j+2] == 'W'){
cnt++;
// cout << i << " " << j << "R\n";
vec[i][j].pb(cnt);
vec[i][j+1].pb(cnt);
vec[i][j+2].pb(cnt);
}
}
}
for(int i =1 ; i<= n ; i++){
for(int j = 1; j <= m ; j++){
if(vec[i][j].size() == 2){
int v = vec[i][j][0] , u = vec[i][j][1] ;
G[v].pb(u);
G[u].pb(v);
}
}
}
int ans1 = 0 ;
for(int i = 1 ;i <= cnt ; i++){
if(mark[i] == 1)continue ;
dfs(i);
ans1 += max(dp[i][0] , dp[i][1]);
}
cout << ans1 << "\n";
}
/*
5 3
RRR
RRG
RGW
GWR
WRR
*/
