#include <bits/stdc++.h>
using namespace std;
void setup()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int dx[4] = {0, 0, -1, 1};
int dy[4] = {1, -1, 0, 0};
int h, w, a, b;
string s[4000];
bool check[4000][4000];
inline void BFS(int x, int y, char c)
{
check[x][y] = true;
for (int i = 0; i < 4; ++i)
{
if (0 <= x + dx[i] && x + dx[i] < h && 0 <= y + dy[i] && y + dy[i] < w &&
s[x + dx[i]][y + dy[i]] == c && !check[x + dx[i]][y + dy[i]])
{
BFS(x + dx[i], y + dy[i], c);
}
}
}
int main()
{
setup();
cin >> h >> w;
for (int i = 0; i < h; ++i)
{
cin >> s[i];
}
for (int i = 0; i < h; ++i)
{
for (int j = 0; j < w; ++j)
{
if (!check[i][j] && s[i][j] != '.')
{
if (s[i][j] == 'R')
{
BFS(i, j, 'R');
a++;
}
else
{
BFS(i, j, 'F');
b++;
}
}
}
}
if (s[0][0] == 'R')
{
cout << (a <= 1 ? 1 : 2) + (b > 0) << "\n";
}
else
{
cout << (b <= 1 ? 1 : 2) + (a > 0) << "\n";
}
return 0;
}
