#include <bits/stdc++.h>
#define pb push_back
#define pll pair<long, long>
#define fr first
#define sc second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
using namespace std;
signed main() {
ios::sync_with_stdio(NULL);
cin.tie(NULL);
cout.tie(NULL);
int h, w;
cin >> h >> w;
char a[h][w];
double f = 0, r = 0;
for (int i = 0; i < h; i++) {
for (int j = 0; j < w; j++) {
cin >> a[i][j];
if (a[i][j] == 'F') f++;
else if (a[i][j] == 'R') r++;
}
}
cout << ceil(f / r) << endl;
}
