#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <cassert>
#include <iostream>
#include <cctype>
#include <sstream>
#include <string>
#include <list>
#include <vector>
#include <queue>
#include <set>
#include <stack>
#include <map>
#include <utility>
#include <numeric>
#include <algorithm>
#include <iterator>
#include <bitset>
#include <complex>
#include <fstream>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vint;
typedef pair<int, int> pint;
#define rep(i, n) REP(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define MSG(a) cout << #a << " " << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
template<class T> T RoundOff(T a){ return int(a+.5-(a<0)); }
template<class T, class C> void chmax(T& a, C b){ if(a < b) a = b; }
template<class T, class C> void chmin(T& a, C b){ if(b < a) a = b; }
template<class T, class C> pair<T, C> mp(T a, C b){ return make_pair(a, b); }

int dx[] = {1, -1, 0, 0};
int dy[] = {0, 0, 1, -1};
int W, H;

void fill(vector<string>& field, int x, int y)
{
	int color = field[y][x];
	field[y][x] = 0;
	
	rep(i, 4)
	{
		int nx = x + dx[i], ny = y + dy[i];
		
		if(0 <= nx && nx < W && 0 <= ny && ny < H && field[ny][nx] == color)
		{
			fill(field, nx, ny);
		}
	}
}

int main()
{
	while(cin >> W >> H && W)
	{
		vector<string> field(H);
		
		rep(i, H)
			cin >> field[i];
		
		int res = 0;
		rep(y, H) rep(x, W)
		{
			if(field[y][x] != 0)
			{
				fill(field, x, y);
				res++;
			}
		}
		
		cout << res << endl;
	}
}