#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define ll long long
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
int h,w,cur;
string s[4005];
void dfs(int i,int j,char c){
cur++;
s[i][j]=(c=='R'?'F':'R');
if(i>0&&s[i-1][j]==c){
dfs(i-1,j,c);
}
if(i<h-1&&s[i+1][j]==c){
dfs(i+1,j,c);
}
if(j>0&&s[i][j-1]==c){
dfs(i,j-1,c);
}
if(j<w-1&&s[i][j+1]==c){
dfs(i,j+1,c);
}
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin>>h>>w;
int cnt=0;
for(int i=0;i<h;i++){
cin>>s[i];
for(int j=0;j<w;j++){
if(s[i][j]!='.'){
cnt++;
}
}
}
int ans=1;
cur=0;
dfs(0,0,s[0][0]);
while(cur<cnt){
cur=0;
dfs(0,0,s[0][0]);
ans++;
}
cout<<ans;
}
