#include <bits/stdc++.h>
using namespace std;
#define N 1000005
#define f first
#define s second
const int inf = INT_MAX;
const int M = 998244353;
int tc = 1, n, dig, m, dp[1000001][3];
char a[3001][3001];
vector <pair<int,int>> v[N];
set <int>s;
bool check(int i,int j,int ok) {
if(ok == 1) return (i > 1 && a[i - 1][j] == 'R' && a[i][j] == 'G' && i < n && a[i + 1][j] == 'W');
return (j > 1 && a[i][j - 1] == 'R' && a[i][j] == 'G' && j < m && a[i][j + 1] == 'W');
}
signed main() {
ios::sync_with_stdio(0);cin.tie(0);
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++) {
v[i + j].push_back({i, j});
s.insert(i + j);
}
}
int ans = 0, inx = 0;
dig = n + m - 1;
for(auto i : s) {
int mx = 0;
inx = 1;
for(auto j : v[i]) {
dp[inx][0] = max({dp[inx - 1][0], dp[inx - 1][1], dp[inx - 1][2]});
for(int k = 1; k <= 2; k++) {
bool ok = 0;
if(check(j.first, j.second, k)) ok = 1;
dp[inx][k] = max({dp[inx - 1][0], dp[inx - 1][k]}) + ok;
mx = max(mx, dp[inx][k]);
}
mx = max(mx,dp[inx][0]);
inx++;
}
ans += mx;
}
cout << ans << endl;
return 0;
}
