// Starcraft 2 enjoyer //
#include <bits/stdc++.h>
// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")
using namespace std;
#define LSOne(X) ((X) & -(X))
const int N = 3e3 + 5;
const int M = 2e5 + 5;
const int LG = 20;
const int INF = 1e9 + 5;
const int K = 2;
const int C = 26;
const int B = 1000;
const int MOD = 998244353;
int n, m, dp[N][2], ans;
char mp[N][N];
inline void solve()
{
cin >> n >> m;
memset(mp, 'a', sizeof(mp));
ans = 0;
for (int x = 1; x <= n; x++)
{
for (int y = 1; y <= m; y++)
{
cin >> mp[x][y];
}
}
for (int s = 2; s <= n + m - 2; s++)
{
for (int x = 1; x <= n; x++)
{
dp[x][0] = dp[x][1] = 0;
}
for (int x = max(1, s - m); x <= n; x++)
{
dp[x][0] = max(dp[x - 1][0], dp[x - 1][1]);
dp[x][1] = dp[x - 1][1];
if (x > 3)
dp[x][1] = max(dp[x - 3][0], dp[x][1]);
int y = s - x;
if (y < 1 || y > m)
continue;
if (mp[x][y] == 'R' && mp[x + 1][y] == 'G' && mp[x + 2][y] == 'W') // 0
{
dp[x][0]++;
}
if (mp[x][y] == 'R' && mp[x][y + 1] == 'G' && mp[x][y + 2] == 'W') // 1
{
dp[x][1]++;
}
}
ans += max(dp[n][0], dp[n][1]);
// cout << ans << " " << s << "\n";
}
cout << ans << "\n";
}
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t = 1;
// cin >> t;
for (int x = 1; x <= t; x++)
{
solve();
}
return 0;
}
