import sys

session = vk.Session()
api = vk.API(session)

def get_partial_group(gid, offset=0):
    if offset == 0:
        return set(api.groups.getMembers(group_id=gid)['users'])
    else:
        return set(api.groups.getMembers(group_id=gid, offset=offset)['users'])

def get_group_mcount(gid):
    return api.groups.getById(group_id=gid, fields='members_count')[0]['members_count']

def get_group(gid):
    n = get_group_mcount(gid)
    result = set()
    for i in range((n + 999) // 1000):
        result = result.union(get_partial_group(gid, i * 1000))
        if len(result) < 2:
            break
    return result

grps = sorted(sys.argv[1:], key=get_group_mcount, reverse=True)

ids = get_group(grps[0])
for _id in grps[1:]:
    ids.intersection_update(get_group(_id))

if len(ids) > 10:
    print('Too many ids: {}'.format(len(ids)))
elif len(ids) > 0:
    print(ids)
else:
    print('No matches')