#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define maxn 4005
#define mod 1000000007
int h, w, dx[] = {0, 0, -1, 1}, dy[] = {-1, 1, 0, 0};
char a[maxn][maxn];
bool vis[maxn][maxn];
void dfs(int x, int y) {
if (x < 1 || x > h || y < 1 || y > w || vis[x][y] == 1) {
return;
}
vis[x][y] = 1;
for (int i = 0; i < 4; i += 1) {
dfs(x + dx[i], y + dy[i]);
}
return;
}
void solve() {
cin >> h >> w;
for (int i = 1; i <= h; i += 1) for (int j = 1; j <= w; j += 1) {
cin >> a[i][j];
}
int ans = 2;
char last_animal = a[1][1];
dfs(1, 1);
for (int i = 1; i <= h; i += 1) for (int j = 1; j <= w; j += 1) {
if (a[i][j] == last_animal && vis[i][j] == 0) {
// cout << i << ' ' << j << '\n';
ans += 1;
dfs(i, j);
}
}
cout << ans;
return;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int test_case = 1;
// cin >> test_case;
for (int i = 1; i <= test_case; i += 1) {
solve();
}
return 0;
}
