#include <bits/stdc++.h>
using namespace std;
#define all(a) a.begin(), a.end()
const int N = 3e3;
char a[N+5][N+5];
int n, m;
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
vector<int> dio[n + m + 2];
for(int i = 1;i <= n; i++){
for(int j = 1;j <= m; j++){
cin >> a[i][j];
dio[i + j].push_back(i);
}
}
int ans = 0;
for(int sum = 2;sum < n + m + 1; sum++){
int sz = dio[sum].size();
int dp[sz + 2][3];
memset(dp, 0, sizeof(dp));
int idx = 1;
for(int i : dio[sum]){
int j = sum - i;
dp[idx][0] = max({dp[idx-1][0], dp[idx-1][1], dp[idx-1][2]});
if(a[i][j] == 'G' && j - 1 > 0 && a[i][j-1] == 'R' && j + 1 <= m && a[i][j+1] == 'W'){
dp[idx][1] = max({dp[idx-1][0], dp[idx-1][1]}) + 1;
}
if(a[i][j] == 'G' && i - 1 > 0 && a[i-1][j] == 'R' && i + 1 <= n && a[i + 1][j] == 'W'){
dp[idx][2] = max({dp[idx-1][0], dp[idx-1][2]}) + 1;
}
idx++;
}
ans += max({dp[sz][0], dp[sz][1], dp[sz][2]});
}
cout << ans;
return 0;
}
