#include <bits/stdc++.h>
using namespace std;
#define int long long
int n,m;
string s[4005];
bool vis[4005][4005];
int ans=0;
int dx[4]={-1,1,0,0}, dy[4]={0,0,-1,1};
deque<pair<int,int>> q;
void solve(){
// freopen("timeline.in","r",stdin);
// freopen("timeline.out","w",stdout);
cin>>n>>m;
for(int i=0; i<n; i++){
cin>>s[i];
}
vis[0][0]=1;
q.push_back({0,0});
char c=s[0][0];
while(!q.empty()){
int x=q.front().first, y=q.front().second;
q.pop_front();
// cout<<x<<" "<<y<<endl;
if(s[x][y]!=c) ans++;
c=s[x][y];
for(int i=0; i<4; i++){
int nx=x+dx[i], ny=y+dy[i];
if(nx>=0 and nx<n and ny>=0 and ny<m and !vis[nx][ny] and s[nx][ny]!='.'){
if(s[nx][ny]!=c){
q.push_back({nx,ny});
}
else{
q.push_front({nx,ny});
}
vis[nx][ny]=1;
}
}
}
cout<<ans+1<<endl;
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(NULL);
int t=1;
// cin>>t;
while(t--) solve();
}
