#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")
using namespace std;
#define int long long
#define pii pair<int,int>
#define ff first
#define ss second
#define sp << " " <<
#define all(cont) cont.begin(),cont.end()
#define vi vector<int>
const int inf = 1e18,N = 3e3+1,MOD = 998244353;
void solve() {
int n,m;
cin >> n >> m;
vector<string> grid(n);
for (auto& it : grid) cin >> it;
auto down = [&](int r,int c) {
if (r+2 >= n || r < 0) return false;
if (c >= m || c < 0) return false;
return grid[r][c] == 'R' && grid[r+1][c] == 'G' && grid[r+2][c] == 'W';
};
auto right = [&](int r,int c) {
if (c+2 >= m) return false;
return grid[r][c] == 'R' && grid[r][c+1] == 'G' && grid[r][c+2] == 'W';
};
int ans = 0;
for (int i=1;i<=n+m-1;i++) {
int topx = (i <= m) ? (1) : (i-m+1);
int topy = (i <= m) ? (i) : (m);
int dp[n+2][3]{};
int mx = 0;
for (int ctr = 1;topx <= n && topy >= 1;topx++,topy--,ctr++) {
for (int j = 0;j<3;j++) {
dp[ctr+1][max(0ll,j-1)] = max(dp[ctr+1][max(0ll,j-1)],
dp[ctr][j]+(j==0 && right(topx-1,topy-1)));
dp[ctr+1][2] = max(dp[ctr+1][2],dp[ctr][j]+down(topx-1,topy-1));
}
}
for (int i = 0;i<=n+1;i++) for (int j = 0;j<3;j++) mx = max(mx,dp[i][j]);
ans+=mx;
}
cout << ans << '\n';
}
int32_t main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#ifdef Dodi
freopen("in.txt","r",stdin);
freopen("out.txt","w",stdout);
#endif
int t = 1;
//cin >> t;
while (t --> 0) solve();
}
