#include <iostream>
#include <string>
using namespace std;
const int MAXN = 4002;
int cx[4] = {+1, 0, -1, 0};
int cy[4] = { 0,-1, 0,+1};
string s[MAXN];
int dfs(int i, int j, char c) {
int sol = 1;
s[i][j] = (c == 'F' ? 'R':'F');
for (int dir = 0; dir < 4; dir++) {
if (s[i+cx[dir]][j+cy[dir]] == c) {
sol += dfs(i+cx[dir], j+cy[dir], c);
}
}
return sol;
}
int main() {
ios::sync_with_stdio(false); cin.tie(0);
int H, W; cin >> H >> W;
s[0] = string(W+1, '#');
for (int i = 1; i <= H; i++) {
cin >> s[i];
s[i] = '#' + s[i] + '#';
}
s[H+1] = string(W+1, '#');
int prev = 0, cur, sol = 0;
while((cur = dfs(1, 1, s[1][1])) != prev) {
prev = cur;
sol++;
}
cout << sol;
return 0;
}
