#include <bits/stdc++.h>
using namespace std;
int main(){
int ans = 0, amount = 0;
int n, m;
char a;
cin >> n >> m;
char board[n][m];
bool board2[n][m];
for (int i = 0; i < n; i++){
for (int j = 0; j < m; j++){
cin >> board[i][j];
if (board[i][j] != '.') amount++;
board2[i][j] = 0;
}
}
char moves = board[0][0];
if (moves == 'F') a = 'R';
if (moves == 'R') a = 'F';
if (moves == '.'){
cout << ans;
return 0;
}
int r = 0;
while (r != amount && ans != 5){
char moves = board[0][0];
if (moves == 'F') a = 'R';
if (moves == 'R') a = 'F';
queue <pair<int, int>> q;
q.push({0, 0});
bool visited[n][m];
for (int i = 0; i < n; i++){
for (int j = 0; j < m; j++){
visited[i][j] = 0;
}
}
while (!q.empty()){
int x = q.front().first;
int y = q.front().second;
board[x][y] = a;
if (board2[x][y] == 0) r++;
board2[x][y] = 1;
q.pop();
if (!visited[x][y]){
visited[x][y] = 1;
if (x != 0 && !visited[x-1][y] && board[x-1][y] == moves) q.push({x-1, y});
if (x != n - 1 && !visited[x+1][y] && board[x+1][y] == moves) q.push({x+1, y});
if (y != 0 && !visited[x][y-1] && board[x][y-1] == moves) q.push({x, y-1});
if (y != m - 1 && !visited[x][y+1] && board[x][y+1] == moves) q.push({x, y+1});
}
}
board[0][0] = a;
ans++;
}
cout << ans;
}
