replacecache.reset();
if (replacecache != null) replacecache.reset();
    int update_pairsid() {        pairsid++;        if (pairsid == MAX_PAIRSID) {            pairsid = 0;            for (bddPair p = pairs; p != null; p = p.next)                p.id = pairsid++;            if (pairsid >= MAX_PAIRSID)                throw new BDDException("Too many pairs!");            replacecache.reset();        }        return pairsid;    }