#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define REV(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
using namespace std;
int n, m;
#define MAXN 4005
char a[MAXN][MAXN];
const int dx[] = {0, 1, 0, -1};
const int dy[] = {-1, 0, 1, 0};
bool start[MAXN][MAXN];
bool vi[MAXN][MAXN];
int group = 0;
bool valid(int i, int j){
return (i >= 1 && i <= n && j >= 1 && j <= m);
}
void DFS(int i, int j){
start[i][j] = 1;
FOR(k, 0, 3){
int ii = i + dy[k];
int jj = j + dx[k];
if (valid(ii, jj) && a[ii][jj] == a[1][1] && start[ii][jj] == 0){
DFS(ii, jj);
}
}
}
void dfs(int i, int j){
vi[i][j] = 1;
FOR(k, 0, 3){
int ii = i + dy[k];
int jj = j + dx[k];
if (valid(ii, jj) && !vi[ii][jj] && (a[ii][jj] == a[i][j] || start[ii][jj] || start[i][j])){
dfs(ii, jj);
}
}
}
void solve(){
cin >> n >> m;
FOR(i, 1, n){
FOR(j, 1, m){
cin >> a[i][j];
}
}
DFS(1, 1);
FOR(i, 1, n){
FOR(j, 1, m){
if (vi[i][j] || a[i][j] == a[1][1] || a[i][j] == '.') continue;
group++;
dfs(i, j);
}
}
int vl = 0;
FOR(i, 1, n){
FOR(j, 1, m){
if (a[i][j] == a[1][1] && !start[i][j]) vl = 1;
}
}
cout << 1 + group + vl;
}
#define task "test"
int32_t main(){
if (fopen(task".inp","r")){
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
solve();
return 0;
}
