// #pragma GCC optimize("O3,Ofast,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define MP make_pair
#define pb push_back
#define REP(i,n) for(int i = 0; (i) < (n); (i)++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
void fastio() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
}
const double EPS = 0.00001;
const int INF = 1e9+500;
const int N = 3e3+5;
const int ALPH = 26;
const int LGN = 25;
constexpr int MOD = 1e9+7;
int n,m,q;
vector<string> a(N, string(N, '0'));
array<array<int,2>, 2> dp, dpn;
int ans = 0;
inline void solve() {
cin>>n>>m;
for(int i = 1; i<=n; i++) {
cin>>a[i];
a[i] = '0' + a[i] + "000";
}
for(int t = 2; t<=n + m; t++) {
dp = {0,0,0,0};
for(int i = max(1, t - m); i <= n; i++) {
int j = t - i;
if(j < 1) break;
if(a[i][j] != 'R') {
dp[0][0] = max(dp[0][0], dp[0][1]);
dp[0][1] = max(dp[1][0], dp[1][1]);
dp[1][0] = dp[1][1] = 0;
continue;
}
for(int f1 = 0; f1<2; f1++) {
for(int f2 = 0; f2<2; f2++) {
dpn[f1][f2] = 0;
if(f1) {
if(a[i + 1][j] == 'G' && a[i + 2][j] == 'W') {
dpn[f1][f2] = max(dp[f2][0], dp[f2][1]) + 1;
}
}
else {
if(!f2 && a[i][j + 1] == 'G' && a[i][j + 2] == 'W') {
dpn[f1][f2] = dp[0][0] + 1;
}
dpn[f1][f2] = max(dpn[f1][f2], max(dp[f2][0], dp[f2][1]));
}
}
}
swap(dpn, dp);
}
ans += max(max(dp[0][0], dp[0][1]) , max(dp[1][0], dp[1][1]) );
}
cout << ans << "\n";
}
signed main() {
//fastio();
int test = 1;
//cin>>test;
while(test--) {
solve();
}
}
