import sys
sys.setrecursionlimit(100000000)


def main():
    process()


def process():
    for data in get_dataset():
        print search(data)


def search(data):
    count = 0
    H = len(data)
    W = len(data[0])
    for i in xrange(H):
        for j in xrange(W):
            if data[i][j] == '.':
                continue
            _search(i, j, H, W, data[i][j], data)
            count += 1
    return count


def _search(i, j, H, W, cell, data):
    data[i][j] = '.'
    for a in xrange(i-1, i+2):
        if -1 < a < H:
            pass
        else:
            continue
        for b in xrange(j-1, j+2):
            if -1 < b < W:
                pass
            else:
                continue

            if a != i and b != j:
                continue

            if data[a][b] == '.':
                continue
            if cell == data[a][b]:
                _search(a, b, H, W, cell, data)
    return


def get_dataset():
    dataset = []
    while True:
        line = raw_input().rstrip().split()
        H = int(line[0])
        if H == 0:
            break

        data = []
        for i in xrange(H):
            data.append(list(raw_input().rstrip()))
        dataset.append(data)
    return dataset


if __name__ == '__main__':
    main()