#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, ok[N][N][2], dp[N * 2][3];
vector<array<int, 2>> e[N * 2];
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') {
ok[i][j][0] = 1;
}
if(a[i][j] == 'G' && a[i - 1][j] == 'R' && a[i + 1][j] == 'W') {
ok[i][j][1] = 1;
}
e[i + j].push_back({i, j});
}
}
int res = 0;
for(int i = 1; i <= n + m; i++) {
int f = (int)e[i].size() - 1;
if(e[i].empty()) continue;
dp[0][0] = ok[e[i][0][0]][e[i][0][1]][0];
dp[0][1] = ok[e[i][0][0]][e[i][0][1]][1];
dp[0][2] = 0;
for(int j = 1; j < (int)e[i].size(); j++) {
int x = e[i][j][0], y = e[i][j][1];
dp[j][2] = max({dp[j - 1][0], dp[j - 1][1], dp[j - 1][2]});
dp[j][0] = max(dp[j - 1][0], dp[j - 1][2]) + ok[x][y][0];
dp[j][1] = max(dp[j - 1][1], dp[j - 1][2]) + ok[x][y][1];
}
// cout << dp[f][1] << '\n';
res += max({dp[f][0], dp[f][1], dp[f][2]});
}
cout << res;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int t = 1;
// cin >> t;
while(t--)
test();
return 0;
}
