import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.ArrayDeque;
import java.util.NoSuchElementException;
import java.util.Queue;
 
public class Main {
    int H,W;
    int[] dy = {1,-1,0,0};
    int[] dx = {0,0,1,-1};
    public void solve() {
        while(true){
            H = nextInt();
            W = nextInt();
 
            if(H + W == 0)break;
            char[][] ch = new char[H][];
            for(int i = 0;i < H;i++){
                ch[i] = next().toCharArray();
            }
 
            boolean[][] used = new boolean[H][W];
            int ans = 0;
            for(int i = 0;i < H;i++){
                for(int j = 0;j < W;j++){
                    if(used[i][j])continue;
                    ans++;
                    Queue<Integer> q = new ArrayDeque<Integer>();
                    q.add(i * 100 + j);
                    while(q.size() > 0){
                        int point = q.poll();
                        int y = point / 100;
                        int x = point % 100;
                        if(used[y][x])continue;
                        used[y][x] = true;
 
                        for(int k = 0;k < 4;k++){
                            int ny = dy[k] + y;
                            int nx = dx[k] + x;
                            if(ny < 0 || nx < 0 || ny >= H || nx >= W)continue;
                            if(ch[i][j] != ch[ny][nx])continue;
                            q.add(ny * 100 + nx);
                        }
                    }
                }
            }
            out.println(ans);
        }
    }
 
    public static void main(String[] args) {
        out.flush();
        new Main().solve();
        out.close();
    }
 
    /* Input */
    private static final InputStream in = System.in;
    private static final PrintWriter out = new PrintWriter(System.out);
    private final byte[] buffer = new byte[2048];
    private int p = 0;
    private int buflen = 0;
 
    private boolean hasNextByte() {
        if (p < buflen)
            return true;
        p = 0;
        try {
            buflen = in.read(buffer);
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (buflen <= 0)
            return false;
        return true;
    }
 
    public boolean hasNext() {
        while (hasNextByte() && !isPrint(buffer[p])) {
            p++;
        }
        return hasNextByte();
    }
 
    private boolean isPrint(int ch) {
        if (ch >= '!' && ch <= '~')
            return true;
        return false;
    }
 
    private int nextByte() {
        if (!hasNextByte())
            return -1;
        return buffer[p++];
    }
 
    public String next() {
        if (!hasNext())
            throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = -1;
        while (isPrint((b = nextByte()))) {
            sb.appendCodePoint(b);
        }
        return sb.toString();
    }
 
    public int nextInt() {
        return Integer.parseInt(next());
    }
 
    public long nextLong() {
        return Long.parseLong(next());
    }
 
    public double nextDouble() {
        return Double.parseDouble(next());
    }
}

Measured memory_bytes: 27096