#include <bits/stdc++.h>
    
using namespace std;
    
typedef long long ll;
    
const int  N = 3e3 + 12, MOD = 998244353, M = 3e6 + 12;
    
char a[N][N];
int n, m, res = 0, res1 = 0, v[N][N], it = 1, h[N][N], dp[M][2];
int T[M][3], sz[M];
void add(int x, int y) {
    T[x][sz[x]++] = y;
    T[y][sz[y]++] = x;
}
bool vis[N * N];
void dfs(int v, int pr = -1) {
    vis[v] = 1;
    dp[v][1] = 1;
    auto work = [&](int to) {
        if(vis[to]) return;
        dfs(to, v);
        dp[v][0] += max(dp[to][0], dp[to][1]);
        dp[v][1] += dp[to][0];
    };
    for(int i = 0; i < sz[v]; i++) {
        int to = T[v][i];   
        if(to == pr || vis[to]) continue;
        dfs(to, v);
    }
}
void test() {
    cin >> n >> m;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            cin >> a[i][j];
        }
    }
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            if(a[i][j] == 'G' && a[i][j - 1] == 'R' && a[i][j + 1] == 'W') {
                h[i][j - 1] = it++;
            }
            if(a[i][j] == 'G' && a[i - 1][j] == 'R' && a[i + 1][j] == 'W') {
                v[i - 1][j] = it++;
            }
        }
    }
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            if(a[i][j] == 'G' && a[i][j - 1] == 'R' && a[i][j + 1] == 'W') {
                if(v[i][j - 1]) {
                    add(v[i][j - 1], h[i][j - 1]);
                }
                if(v[i - 1][j]) {
                    add(v[i - 1][j], h[i][j - 1]);
                }
                if(v[i - 2][j + 1]) {
                    add(v[i - 2][j + 1], h[i][j - 1]);
                }
            }
        }
    }
    for(int i = 1; i < it; i++) {
        if(!vis[i]) {
            dfs(i);
            res += max(dp[i][0], dp[i][1]);
        }
    }
    cout << res << '\n';
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); 
    
    int t = 1; 
    // cin >> t;
    
    while(t--) 
        test();
    
    return 0;
}