#include<bits/stdc++.h>
using namespace std;
const int N = 4020;
int foxVis[N][N], rabbitVis[N][N];
int h,w,fox;
string forest[N];
void dfs( int x, int y ){
if( x < 0 || x >= h || y < 0 || y >= w || forest[h][w] == '.' ) return;
if( fox ){
if( foxVis[x][y] == 1 ) return;
foxVis[x][y] = 1;
}else{
if( rabbitVis[x][y] == 1 ) return;
rabbitVis[x][y] = 1;
}
dfs(x+1,y);
dfs(x-1,y);
dfs(x,y+1);
dfs(x,y-1);
}
int main(){
cin >> h >> w;
for( int i = 0 ; i < h ; i++ ) cin >> forest[i];
int f = 0, r = 0;
for( int i = 0 ; i < h ; i++ ){
for( int j = 0 ; j < w ; j++ ){
if( forest[i][j] == 'F' ) f = 1;
else if( forest[i][j] == 'R' ) r = 1;
}
}
int ans = 0, ans1 = 0, ans2 = 0;
for( int i = 0 ; i < h ; i++ ){
for( int j = 0 ; j < w ; j++ ){
if( forest[i][j] == '.' || rabbitVis[i][j] ) continue;
ans1++;
dfs(i,j);
}
}
fox = 1;
for( int i = 0 ; i < h ; i++ ){
for( int j = 0 ; j < w ; j++ ){
if( forest[i][j] == '.' || foxVis[i][j] ) continue;
ans2++;
dfs(i,j);
}
}
if( f ) ans += ans2;
if( r ) ans += ans1;
cout << ans << endl;
return 0;
}
