#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pi> vpi;
typedef vector<vi> vvi;
const int inf = 0x3f3f3f3f;
const ll linf = 123456789012345678;
const ll mod = 998244353;
#pragma GCC optimize("Ofast")
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " = " << x << endl
int n, m;
vvi a;
int main(){
cin >> n >> m;
a = vvi(n, vi(m));
for(int i = 0; i < n; i++){
string s;
cin >> s;
for(int j = 0; j < m; j++){
if(s[j] == 'G') a[i][j] = 1;
else if(s[j] == 'W') a[i][j] = 2;
}
}
int ans = 0;
for(int k = 0; k < n+m-1; k++){
int c = k;
int r = 0;
if(c >= m){
r = c-m+1;
c = m-1;
}
vvi dp(min(c+1,n-r)+1, vi(3));
int pos = min(c,n-r-1);
while(r < n && c >= 0){
dp[pos][0] = dp[pos+1][0];
dp[pos][1] = dp[pos+1][0];
dp[pos][2] = dp[pos+1][1];
if(c + 2 < m && a[r][c] == 0 && a[r][c+1] == 1 && a[r][c+2] == 2){
dp[pos][0] = max(dp[pos][0], dp[pos+1][2] + 1);
dp[pos][1] = max(dp[pos][1], dp[pos+1][2] + 1);
dp[pos][2] = max(dp[pos][2], dp[pos+1][2] + 1);
}
if(r + 2 < n && a[r][c] == 0 && a[r+1][c] == 1 && a[r+2][c] == 2){
dp[pos][0] = max(dp[pos][0], dp[pos+1][0] + 1);
}
r++;
c--;
pos--;
}
ans += dp[0][0];
}
cout << ans << "\n";
}
