#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define pii pair<int, int>
#define pll pair<ll, ll>
#define st first
#define nd second
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define debug false
const int MAXN = 3000 + 17;
char a[MAXN][MAXN];
int dp[MAXN];
int dppion[MAXN];
int dppoziom[MAXN];
int main () {
ios::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 >> a[i][j];
}
}
int wyn = 0;
for (int i = 1; i <= n + m - 1; i ++) {
int ind = 1;
for (int j = min(i, n); j >= 0; j --) {
if (i - j > m) {
break;
}
dppion[ind] = max(dp[ind - 1], dppion[ind - 1]);
dppoziom[ind] = max(dp[ind - 1], dppoziom[ind - 1]);
dp[ind] = max(dppion[ind], dppoziom[ind]);
if (j - 1 >= 1 && j + 1 <= n) {
if (a[j - 1][i - j] == 'R' && a[j][i - j] == 'G' && a[j + 1][i - j] == 'W') {
dppion[ind] ++;
}
}
if (i - j - 1 >= 1 && i - j + 1 <= m) {
if (a[j][i - j - 1] == 'R'&& a[j][i - j] == 'G' && a[j][i - j + 1] == 'W') {
dppoziom[ind] ++;
}
}
//cout << i << " " << ind << ": " << dp[ind] << " " << dppion[ind] << " " << dppoziom[ind] << "\n";
ind ++;
}
wyn += max(dp[ind - 1], max(dppion[ind - 1], dppoziom[ind - 1]));
memset(dp, 0, sizeof(dp));
memset(dppoziom, 0, sizeof(dppoziom));
memset(dppion, 0, sizeof(dppion));
}
cout << wyn << "\n";
return 0;
}
