#include <bits/stdc++.h>
#include <bits/extc++.h>
#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define iceil(a, b) (((a) + (b) - 1) / (b))
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
if(pvaspace) b << " "; pvaspace=true;\
b << pva;\
}\
b << "\n";}
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;
const ll MOD = 1000000007;
const ll MAX = 2147483647;
template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
return o << '(' << p.F << ',' << p.S << ')';
}
int main(){
StarBurstStream
int n, m;
cin >> n >> m;
vector<string> a(n + 2);
a[0] = a[n + 1] = string(m + 2, ' ');
for(int i = 1; i <= n; i++){
cin >> a[i];
a[i] = ' ' + a[i] + ' ';
}
vector<vector<int>> dp0(n + 2, vector<int>(m + 2));
vector<vector<int>> dp1(n + 2, vector<int>(m + 2));
vector<int> ans(n + m + 1);
for(int i = n; i >= 1; i--){
for(int j = 1; j <= m; j++){
dp0[i][j] = dp1[i][j] = max(dp0[i + 1][j - 1], dp1[i + 1][j - 1]);
if(a[i][j] != 'G') continue;
// cerr << i << " " << j << " " << a[i - 1][j] << " " << a[i + 1][j] << " " << a[i][j - 1] << " " << a[i][j + 1] << "\n";
if(a[i - 1][j] == 'R' && a[i + 1][j] == 'W') dp0[i][j] = max(dp0[i][j], dp0[i + 1][j - 1] + 1);
if(a[i][j - 1] == 'R' && a[i][j + 1] == 'W') dp1[i][j] = max(dp1[i][j], dp1[i + 1][j - 1] + 1);
ans[i + j] = max({ans[i + j], dp0[i][j], dp1[i][j]});
}
}
// for(int i = 1; i <= n; i++) printv(dp0[i], cerr);
// for(int i = 1; i <= n; i++) printv(dp1[i], cerr);
int total = 0;
for(int i : ans) total += i;
cout << total << "\n";
return 0;
}
