#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int h, w;
cin >> h >> w;
vector<vector<char>> grid(h, vector<char>(w));
for (int i = 0; i < h; i++) {
for (int j = 0; j < w; j++) {
cin >> grid[i][j];
}
}
int ans = 0;
bool done = false;
char last = grid[0][0];
queue<pair<int, int>> q;
vector<vector<bool>> vis(h, vector<bool>(w, false));
for (int i = 0; i < h; i++) {
for (int j = 0; j < w; j++) {
if (!vis[i][j] && grid[i][j] != '.') {
q.push({i, j});
vis[i][j] = true;
if (grid[i][j] == last)
ans++;
else if (!done) {
ans++;
done = true;
}
}
while (!q.empty()) {
auto [x, y] = q.front();
q.pop();
if (x + 1 < h && grid[x + 1][y] == grid[i][j] && !vis[x + 1][y]) {
vis[x + 1][y] = true;
q.push({x + 1, y});
}
if (x - 1 >= 0 && grid[x - 1][y] == grid[i][j] && !vis[x - 1][y]) {
vis[x - 1][y] = true;
q.push({x - 1, y});
}
if (y + 1 < w && grid[x][y + 1] == grid[i][j] && !vis[x][y + 1]) {
vis[x][y + 1] = true;
q.push({x, y + 1});
}
if (y - 1 >= 0 && grid[x][y - 1] == grid[i][j] && !vis[x][y - 1]) {
vis[x][y - 1] = true;
q.push({x, y - 1});
}
}
}
}
cout << ans << endl;
}
