//I love ManchesterUnited
#include<bits/stdc++.h>
using namespace std;
#define love ManchesterUnited
#define int long long
#define pb push_back
#define FOR(i,a,b) for (int i=(a); i<=(b); i++)
#define FORD(i,b,a) for (int i=(b); i>=(a); i--)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define ALL(a) (a).begin(),(a).end()
#define ii pair<int,int>
#define iii pair<int,ii>
#define fi first
#define se second
#define endl '\n'
#define MASK(x) (1 << (x))
#define BIT(mask,i) ((mask >> i) & 1)
typedef long long ll;
template<class X, class Y>
bool minimize(X &x, const Y &y) {
if (x > y) {
x = y;
return true;
} else return false;
}
template<class X, class Y>
bool maximize(X &x, const Y &y) {
if (x < y) {
x = y;
return true;
} else return false;
}
template<class T>
T Abs(const T &x) {
return (x < 0 ? -x : x);
}
//___________________________________________________________________________________________________________________________________________________________
// CODE:
mt19937 rd(time(0) );
int Rand(int l,int r){
return l + rand() % (r - l + 1);
}
const int N = 3005;
const int MOD = 1e9 + 7;
int n,m;
char a[N][N];
bool cnt[N][N];
int32_t main()
{
// freopen("test.inp","r",stdin);
// freopen("test.out","w",stdout);
ios::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> m;
FOR(i,1,n) FOR(j,1,m) cin >> a[i][j];
vector <ii> vec;
int res = 0;
FOR(tc,1,1000){
int ans = 0;
memset(cnt,0,sizeof cnt);
FOR(i,1,n) FOR(j,1,m) {
if (a[i][j] == 'R') {
int ok = Rand(0,1);
if (ok) {
if (a[i][j + 1] == 'G' && a[i][j + 2] == 'W' && !cnt[i][j + 1] && !cnt[i][j + 2]){
ans++;
cnt[i][j + 2] = 1; cnt[i][j + 1] = 1;
}
if (a[i + 1][j] == 'G' && a[i + 2][j] == 'W' && !cnt[i + 1][j] && !cnt[i + 2][j]){
ans++;
cnt[i + 1][j] = 1; cnt[i + 2][j] = 1;
}
} else {
if (a[i + 1][j] == 'G' && a[i + 2][j] == 'W' && !cnt[i + 1][j] && !cnt[i + 2][j]){
ans++;
cnt[i + 1][j] = 1; cnt[i + 2][j] = 1;
}
if (a[i][j + 1] == 'G' && a[i][j + 2] == 'W' && !cnt[i][j + 1] && !cnt[i][j + 2]){
ans++;
cnt[i][j + 2] = 1; cnt[i][j + 1] = 1;
}
}
}
}
res = max(res,ans);
}
cout << res << endl;
}
