#include <bits/stdc++.h>
using namespace std;
const int N = 3005;
int A[N][N],dp[N][N];
int main() {
int n,m;
cin>>n>>m;
for(int i = 1;i<=n;i++) {
for(int j = 1;j<=m;j++) {
char c;
cin>>c;
if(c=='R')A[i][j]=1;
else if (c == 'G') A[i][j] = 2;
else A[i][j] = 3;
}
}
for(int i = 1;i<=n;i++) {
for(int j = 1;j<=m;j++) {
// drag
dp[i][j] += dp[i-1][j] + dp[i][j-1] - dp[i-1][j-1];
// hor
int c1 = (A[i][j] == 1 && A[i][j+1] == 2 && A[i][j+2] == 3);
int c2 = (A[i][j] == 1 && A[i+1][j] == 2 && A[i+2][j] == 3);
if(c1)dp[i][j+2]++;
if(c2)dp[i+2][j]++;
if(c1&&c2)dp[i+2][j+2]--;
}
}
// for(int i = 1;i<=n;i++) {
// for(int j = 1;j<=m;j++) {
// cout << dp[i][j] << " ";
// }cout << "\n";
// }
cout<<dp[n][m];
}
