#include <bits/stdc++.h>
using namespace std;
struct point {
int x, y;
};
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, m;
cin >> n >> m;
char trace[n][m];
int distance[n][m];
for(int loop = 0; loop < n; ++loop) {
for(int looping = 0; looping < m; ++looping) {
cin >> trace[loop][looping];
distance[loop][looping] = 1e9;
}
}
char current;
int num = 0;
vector<point> stack;
queue<point> q;
distance[0][0] = 1;
q.push({0, 0});
while(q.size() > 0) {
while(q.size() > 0) {
stack.push_back(q.front());
q.pop();
}
num++;
current = trace[stack[0].x][stack[0].y];
while(stack.size() > 0) {
point enCours = stack.back();
stack.pop_back();
if(enCours.x > 0) {
if(distance[enCours.x-1][enCours.y] == 1e9) {
if(trace[enCours.x-1][enCours.y] == current) {
stack.push_back({enCours.x-1, enCours.y});
distance[enCours.x-1][enCours.y] = num;
}
else if(trace[enCours.x-1][enCours.y] != '.') {
q.push({enCours.x-1, enCours.y});
distance[enCours.x-1][enCours.y] = num+1;
}
}
}
if(enCours.x < n-1) {
if(distance[enCours.x+1][enCours.y] == 1e9) {
if(trace[enCours.x+1][enCours.y] == current) {
stack.push_back({enCours.x+1, enCours.y});
distance[enCours.x+1][enCours.y] = num;
}
else if(trace[enCours.x+1][enCours.y] != '.') {
q.push({enCours.x+1, enCours.y});
distance[enCours.x+1][enCours.y] = num+1;
}
}
}
if(enCours.y > 0) {
if(distance[enCours.x][enCours.y-1] == 1e9) {
if(trace[enCours.x][enCours.y-1] == current) {
stack.push_back({enCours.x, enCours.y-1});
distance[enCours.x][enCours.y-1] = num;
}
else if(trace[enCours.x][enCours.y-1] != '.') {
q.push({enCours.x, enCours.y-1});
distance[enCours.x][enCours.y-1] = num+1;
}
}
}
if(enCours.y < m-1) {
if(distance[enCours.x][enCours.y+1] == 1e9) {
if(trace[enCours.x][enCours.y+1] == current) {
stack.push_back({enCours.x, enCours.y+1});
distance[enCours.x][enCours.y+1] = num;
}
else if(trace[enCours.x][enCours.y+1] != '.') {
q.push({enCours.x, enCours.y+1});
distance[enCours.x][enCours.y+1] = num+1;
}
}
}
}
}
cout << num << '\n';
}
