#include <bits/stdc++.h>
#define int long long
using namespace std;
const int N = 3e3 + 42;
char c[N][N];
int n, m, dp[N][N][2];
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
n += 3;
for(int i = 0; i < N; i++)
for(int j = 0; j < N; j++)
c[i][j] = '#';
for(int i = 3; i < n; i++)
for(int j = 0; j < m; j++)
cin >> c[i][j];
int ans = 0;
for(int i = 3; i < n; i++) {
for(int j = 0; j < m; j++) {
if(c[i][j] == 'R' && c[i+1][j] == 'G' && c[i+2][j] == 'W') {
dp[i][j][0] = max(dp[i-1][j+1][0], dp[i-1][j+1][1]) + 1;
}
if(c[i][j] == 'R' && c[i][j+1] == 'G' && c[i][j+2] == 'W') {
dp[i][j][1] = max(dp[i-3][j+3][0], dp[i-1][j+1][1]) + 1;
}
dp[i][j][1] = max(dp[i][j][1], dp[i-2][j+2][0]);
dp[i][j][1] = max(dp[i][j][1], dp[i-1][j+1][1]);
dp[i][j][0] = max(dp[i][j][0], dp[i][j][1]);
dp[i][j][0] = max(dp[i][j][0], dp[i-1][j+1][0]);
if(i == n-1 || j == 0)
ans += dp[i][j][0];
}
}
cout << ans << '\n';
}
