#include <iostream>
#include <vector>
#define pb push_back
#define endl '\n'
using namespace std;
const int MAXN = 3e7+100;
vector<int> adj[MAXN];
char tp[MAXN];
int h, w, n;
string mat[4010];
int cnt;
bool used[MAXN];
void dfs(int v, int ld){
cout << v << endl;
used[v] = 1;
for(int u : adj[v]){
if(used[u]) continue;
if(tp[u] == tp[v] || tp[u] == '-' || tp[v] == '-') dfs(u, ld);
else if(tp[v] != '-'){
adj[u].pb(n+ld);
adj[n+ld].pb(u);
// cout << u << "<->" << n+ld << endl;
}
}
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);
cin >> h >> w;
n = h*w;
for(int i=0;i<h; i++) cin >> mat[i];
for(int i=0; i<h; i++){
for(int j=0; j<w; j++){
int v, u, u_;
v = (i*w) + j;
u = (i+1)*w + j;
u_ = i*w + j + 1;
if(tp[v] == '.') continue;
if(i < (h-1) && tp[u] != '.'){
adj[v].pb(u);
adj[u].pb(v);
}
if(j < (w-1) && tp[u] != '.'){
adj[v].pb(u_);
adj[u_].pb(v);
}
tp[v] = mat[i][j];
}
}
for(int i=0; i<n; i++){
if(used[i] || tp[i] == '.') continue;
used[i] = 1;
tp[cnt + n] = '-';
// dfs(i, cnt);
cnt++;
}
cout << cnt << endl;
return 0;
}
