#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const int maxn = 3000 + 10;
const int inf = 1e9;
string s[maxn];
int dp[maxn][maxn][2];
int main(){
ios_base::sync_with_stdio(false);
int n, m;
cin >> n >> m;
for (int i = 0; i < n; i++)
cin >> s[i];
int answer = 0;
for (int i = 0; i < n; i++){
for (int j = 0; j < m; j++){
if (s[i][j] != 'G')
continue;
int can = 0;
if (i > 0 and i < n - 1 and s[i - 1][j] == 'R' and s[i + 1][j] == 'W')
can |= 1;
if (j > 0 and j < m - 1 and s[i][j - 1] == 'R' and s[i][j + 1] == 'W')
can |= 2;
if (i > 0 and j < m - 1)
dp[i][j][0] = dp[i][j][1] = max(dp[i-1][j+1][0], dp[i-1][j+1][1]);
if (can & 1){
int t = ((i > 0 and j < m - 1) ? dp[i-1][j+1][0] : 0);
dp[i][j][0] = max(dp[i][j][0], t + 1);
}
if (can & 2){
int t = ((i > 0 and j < m - 1) ? dp[i-1][j+1][1] : 0);
dp[i][j][1] = max(dp[i][j][1], t + 1);
}
if (i == n - 1 or j == 0 or s[i+1][j-1] != 'G')
answer += max(dp[i][j][0], dp[i][j][1]);
}
}
cout << answer << '\n';
}
