#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ff(i,a,b) for(int i=a;i<=b;i++)
#define fb(i,b,a) for(int i=b;i>=a;i--)
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 3005;
const int inf = 1e9 + 5;
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k) print the k-th smallest number in os(0-based)
int n, m;
char mat[maxn][maxn];
bool ok[maxn][maxn][2];
int dp[maxn][3];
int main()
{
ios::sync_with_stdio(false);
cout.tie(nullptr);
cin.tie(nullptr);
cin >> n >> m;
ff(i,1,n)ff(j,1,m)cin >> mat[i][j];
ff(i,1,n) {
ff(j,1,m) {
if(mat[i][j] == 'G') {
if(i > 1 && i < n && mat[i - 1][j] == 'R' && mat[i + 1][j] == 'W')ok[i][j][0] = 1;
if(j > 1 && j < m && mat[i][j - 1] == 'R' && mat[i][j + 1] == 'W')ok[i][j][1] = 1;
}
}
}
int rez = 0;
ff(a,1,n + m) {
memset(dp, 0, sizeof(dp));
ff(i,1,n) {
if(a - i >= 1 && a - i <= m) {
int j = a - i;
dp[i][0] = max({dp[i - 1][0], dp[i - 1][1], dp[i - 1][2]});
if(ok[i][j][0])dp[i][1] = max(dp[i - 1][0], dp[i - 1][1]) + 1;
if(ok[i][j][1])dp[i][2] = max(dp[i - 1][0], dp[i - 1][2]) + 1;
} else ff(j,0,2)dp[i][j] = dp[i - 1][j];
}
rez += max({dp[n][0], dp[n][1], dp[n][2]});
}
cout << rez << endl;
return 0;
}
/**
3 4
RGWR
GRGG
RGWW
// probati bojenje sahovski ili slicno
**/
