#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
const int mxN = 3e3 + 5;
ll n,dp[mxN][mxN][3],ii,jj,m;
char a[mxN][mxN];
bool check(ll i, ll j, char ch){
if(i >= n or i < 0 or j >= m or j < 0) return false;
return (a[i][j] == ch);
}
void f(ll i, ll j){
while(i >= 0 and j < m){
ii = i;
jj = j;
if(j > 0 and i + 1 < n){
ll x = max(dp[i + 1][j - 1][1], dp[i + 1][j - 1][0]);
dp[i][j][2] = max(x, dp[i + 1][j - 1][2]);
}
if(a[i][j] != 'R'){
i--;
j++;
continue;
}
// 0 -- > R
// 1 -- > D
// 2 -- >
if(check(i + 1, j, 'G') and check(i + 2, j, 'W')){
if(j > 0 and i + 1 < n){
dp[i][j][1] = dp[i + 1][j - 1][1] + 1;
}
else dp[i][j][1] = 1;
if(j > 1 and i + 2 < n){
dp[i][j][1] = max(dp[i][j][1], max(dp[i + 2][j - 2][1], dp[i + 2][j - 2][2]) + 1);
}
}
if(check(i, j + 1, 'G') and check(i, j + 2, 'W')){
dp[i][j][0] = dp[i][j][2] + 1;
}
i--;
j++;
}
}
int main(){
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
for(int i = 0; i < n; i++){
for(int j = 0; j < m; j++) cin >> a[i][j];
}
ll ans = 0;
for(int i = 0; i < n; i++){
f(i, 0);
ans += max(dp[ii][jj][0], max(dp[ii][jj][1], dp[ii][jj][2]));
// cout << i << ' ' << ii << ' ' << jj << ' ' << max(dp[ii][jj][0], dp[ii][jj][1]) << '\n';
}
for(int j = 1; j < m; j++){
f(n - 1, j);
ans += max(dp[ii][jj][0], max(dp[ii][jj][1], dp[ii][jj][2]));
}
cout << ans << '\n';
}
