#include <bits/stdc++.h>
using namespace std;
/***
Last animal to enter the maze is in mat[0][0]
***/
const int MAXN = 4000;
const int ox[] = {0, 1, 0, -1};
const int oy[] = {1, 0, -1, 0};
int n, m;
char mat[MAXN + 1][MAXN + 1];
bool used[MAXN + 1][MAXN + 1];
bool inside(const int x, const int y) {
if (x >= 0 && y >= 0 && x < n && y < m) {
return true;
}
return false;
}
int main() {
cin >> n >> m;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
cin >> mat[i][j];
}
}
const char target = mat[0][0];
queue<pair<int, int>> q;
int ans = 0, add = 0;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (!used[i][j] && mat[i][j] == target) {
ans++;
q.push(make_pair(i, j));
while (!q.empty()) {
int x, y;
tie(x, y) = q.front();
q.pop();
for (int k = 0; k < 4; k++) {
int nx = x + ox[k];
int ny = y + oy[k];
if (inside(nx, ny) && !used[nx][ny] && mat[nx][ny] == target) {
used[nx][ny] = true;
q.push(make_pair(nx, ny));
}
}
}
} else if (mat[i][j] != target) {
add = 1;
}
}
}
cout << ans + add << "\n";
return 0;
}
