#include <iostream>
#include <vector>
#include <array>
#include <algorithm>
using namespace std;
int n, m;
vector<vector<int>> grid;
vector<vector<bool>> horizontal;
vector<vector<bool>> vertical;
vector<vector<array<bool, 2>>> checked;
struct Dango{
int x;
int y;
int d; // 0 = vertical, 1 = horizontal
bool operator<(Dango other){
if (x == other.x){
return d < other.d;
}
return x < other.x;
}
};
vector<Dango> now;
void grow(int x, int y, int d){
checked[y][x][d] = true;
now.push_back(Dango{x, y, d});
if (d == 1){
if (y-1 >= 0 && x+1 < m && vertical[y-1][x+1] && !checked[y-1][x+1][!d]){
grow(x+1, y-1, !d);
}
if (vertical[y][x] && !checked[y][x][!d]){
grow(x, y, !d);
}
if (x-1 >= 0 && y+1 < n && vertical[y+1][x-1] && !checked[y+1][x-1][!d]){
grow(x-1, y+1, !d);
}
}
if (d == 0){
if (y-1 >= 0 && x+1 < m && horizontal[y-1][x+1] && !checked[y-1][x+1][!d]){
grow(x+1, y-1, !d);
}
if (horizontal[y][x] && !checked[y][x][!d]){
grow(x, y, !d);
}
if (x-1 >= 0 && y+1 < n && horizontal[y+1][x-1] && !checked[y+1][x-1][!d]){
grow(x-1, y+1, !d);
}
}
}
int ile(){
sort(now.begin(), now.end());
int w = 1;
array<bool, 2> best = {false, false};
best[now[0].d] = true;
for (int i=1; i<size(now); i++){
int d = now[i].d;
if (best[d]){
w++;
best = {false, false};
}
else{
best[d] = true;
}
}
return w;
}
int main(){
cin >> n >> m;
checked = vector<vector<array<bool, 2>>>(n, vector<array<bool, 2>>(m, {false, false}));
for (int i=0; i<n; i++){
grid.push_back(vector<int> {});
for (int j=0; j<m; j++){
char a;
cin >> a;
if (a == 'R'){
grid[i].push_back(0);
}
if (a == 'G'){
grid[i].push_back(1);
}
if (a == 'W'){
grid[i].push_back(2);
}
}
}
if (m >= 3){
for (int j=0; j<n; j++){
horizontal.push_back(vector<bool> {false});
for (int i=1; i<m-1; i++){
if (grid[j][i-1] == 0 && grid[j][i] == 1 && grid[j][i+1] == 2){
horizontal[j].push_back(true);
}
else{
horizontal[j].push_back(false);
}
}
horizontal[j].push_back(false);
}
}
if (n >= 3){
vertical.push_back(vector<bool> {});
for (int i=0; i<m; i++){
vertical[0].push_back(false);
}
for (int j=1; j<n-1; j++){
vertical.push_back(vector<bool> {});
for (int i=0; i<m; i++){
if (grid[j-1][i] == 0 && grid[j][i] == 1 && grid[j+1][i] == 2){
vertical[j].push_back(true);
}
else{
vertical[j].push_back(false);
}
}
}
vertical.push_back(vector<bool> {});
for (int i=0; i<m; i++){
vertical[n-1].push_back(false);
}
}
if (m < 3 && n < 3){
cout << 0;
return 0;
}
if (m < 3){
int w = 0;
for (int i=0; i<n; i++){
for (int j=0; j<m; j++){
if (vertical[i][j]){
w++;
}
}
}
cout << w;
return 0;
}
if (n < 3){
int w = 0;
for (int i=0; i<n; i++){
for (int j=0; j<m; j++){
if (horizontal[i][j]){
w++;
}
}
}
cout << w;
return 0;
}
int wynik = 0;
for (int i=0; i<n; i++){
for (int j=0; j<m; j++){
if (vertical[i][j] && !checked[i][j][0]){
grow(j, i, 0);
wynik += ile();
now.clear();
}
if (horizontal[i][j] && !checked[i][j][1]){
grow(j, i, 1);
wynik += ile();
now.clear();
}
}
}
cout << wynik;
}
