import sys


def find_parent(index, parents):
    if index != parents[index]:
        parents[index] = find_parent(parents[index], parents)
    return parents[index]


def main():
    with open(sys.argv[1]) as f:
        while True:
            N, M = map(int, f.readline().split())
            if N == 0 and M == 0:
                break
            parents = list(range(N + 1))
            for _ in range(M):
                i, j = map(int, f.readline().split())
                parents[find_parent(i, parents)] = find_parent(j, parents)
            print(len(set(find_parent(x, parents) for x in range(1, N + 1))))


if __name__ == "__main__":
    main()