#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
#define f first
#define s second
#define pb push_back
#define ep emplace
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define uniquev(v) sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define mem(f,x) memset(f , x , sizeof(f))
#define sz(x) (int)(x).size()
#define __lcm(a, b) (1ll * ((a) / __gcd((a), (b))) * (b))
#define mxx *max_element
#define mnn *min_element
#define cntbit(x) __builtin_popcountll(x)
#define len(x) (int)(x.length())
const int N = 3e3 + 100;
char mat[N][N];
int f[N][3];
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, m;
cin >> n >> m;
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= m; j++) {
cin >> mat[i][j];
}
}
int ans = 0;
for (int dig = 1; dig <= m + n; dig++) {
int mn = max(1, dig - m), mx = min(n, max(1, dig - 1));
for (int i = 0; i <= dig; i++)
f[i][0] = f[i][1] = f[i][2] = 0;
for (int x = mn; x <= mx; x++) {
int y = dig - x;
if (mat[x][y] == 'G') {
if (mat[x - 1][y] == 'R' && mat[x + 1][y] == 'W')
f[x][1] = max(f[x - 1][1], f[x - 1][0]) + 1;
if (mat[x][y - 1] == 'R' && mat[x][y + 1] == 'W')
f[x][2] = max(f[x - 1][2], f[x - 1][0]) + 1;
}
f[x][0] = max({f[x - 1][0], f[x - 1][1], f[x - 1][2]});
}
ans += max({f[mx][0], f[mx][1], f[mx][2]});
}
cout << ans << '\n';
return 0;
}
