#include<bits/stdc++.h>
// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
typedef long long ll;
typedef long double ld;
#define SPEED ios_base::sync_with_stdio(false); cin.tie(0), cout.tie(0)
#define rall(v) (v).rbegin(),(v).rend()
#define all(v) (v).begin(),(v).end()
#define OK cerr<<"OK"<<endl<<flush
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define F first
#define S second
#define y0 jahdakdh
#define y1 jahsadakdakdh
#define endl '\n'
using namespace std;
const ll MOD=1e9+7;
// mt19937 rng(std::chrono::system_clock::now().time_since_epoch().count());
int n, m, ans;
char a[4005][4005];
bool used[4005][4005];
void dfs(int x, int y)
{
used[x][y]=1;
if(x+1<n and a[x+1][y]==a[x][y] and !used[x+1][y]) dfs(x+1, y);
if(x-1>=0 and a[x-1][y]==a[x][y] and !used[x-1][y]) dfs(x-1, y);
if(y+1<m and a[x][y+1]==a[x][y] and !used[x][y+1]) dfs(x, y+1);
if(y-1>=0 and a[x][y-1]==a[x][y] and !used[x][y-1]) dfs(x, y-1);
}
int main()
{
SPEED;
cin>>n>>m;
for(int i=0; i<n; i++)
for(int j=0; j<m; j++)
cin>>a[i][j];
for(int i=0; i<n; i++)
for(int j=0; j<m; j++)
{
if(a[i][j]==a[0][0] and !used[i][j]) ans++, dfs(i, j);
}
cout<<ans+1<<endl;
return 0;
}
